AITAH for not accepting parents terms of engagement with my kids?

Okay so there's a long history with many examples but basically for 6 years my parents spent more time with my sister and her kids than mine, for 3 of those years my mom moved in with my sister for most of the year to take care of her kids full time while she was doing school (including 2 new births during this period). My parents allowed my wife and I to live with them for 22 months while I was doing school, but my mom was gone for most of it and there was minimal child help or time spent other than little check-ins. Even before this time, my mom spent more time with my sisters kids, and after. My mom always said I was the "easy" child she didn't have to worry about. Some things she said throughout this time were that she was glad she didn't have to be "mom" to our kids like my sisters, etc. However, being a good grandma requires spending enough time with the kids without the parents present, it's not about babysitting, it's about bond building. They did some things over the years like watched kids for trips, the rare date night, and some time postpartum, but it was never even close to the range of my sister. It started to compound in hurtfulness because we noticed her being more attached to my sisters kids, treating them in our view as if they were more important or a given of care where as anything she did for us was a huge gift or bestowment, even a visit of 2 nights when we moved away. She also helped my sister more postpartum than us, even though my wife doesn't have a relationship with her parents because of drug addiction and child neglect. We went through similar struggles, by my sisters were always deemed more important. There are so many examples I could give but stuff like my wife being expected to deal with everything solo or just with me but my sister being supported for all manner of things (even when I was a worse husband than the "bad" husband they claimed she had), my mom making my wife's 30th birthday about my sister, praising sister profusely for showing up for 2 hours while my wife had just watched her kids for a week, telling my wife I need to move on because I'm a better person after an affair but enabling my sister to leave her husband by apartment shopping after she had had an affair, resulting in her giving him almost full custody. Now there was a time when I was 18 and I was actually in the affair (nobody knew at the time) when I was threatening to leave and my parents did support my wife and daughter during THIS stage (I am a different person now), telling my wife my sister's life is harder than hers when she had hyperemesis, SPD pregnancy pain, and an absent husband with two toddlers in a city all alone with my mom just coming to visit every few months for 2 nights but staying at my sisters for months, etc so much more. All of this has resulted in more bonding time for my sisters kids, and because its our kids only chance at a grandma, thats what we care about.

Even after this stage, she'd visit sister for longer but just as often etc, continuing the bond. One time she even brought sisters kids to our house on her once every 2 or 3 month visit for 2 nights and spent most of the time focusing on them. I finally said something to my dad (who never de-prioritized us in deed but often backed up my mom or sister), and this led to my mom triangulating me with my sister and thus deeming my wife as the "grudge holder" and us as "ungrateful" and that she had to bend over backwards to make things "fair". At this point our kids barely had any relationship with her, it was mostly performative. We tried many things to make her happy and make her want to spend more time with us including making visits adult focused with stuff she liked (wine visits etc), not asking for dates, praising her, etc but it didn't work much. When we had real catastrophic needs which were always my sisters excuse, we didn't get the same response or reaction. They eventually tried to balance out time but still hid visits to sister and her kids to my moms house so we still feel it was unbalanced though they deny. My mom has said "I can't even imagine confronting my parents this way!" and got angry and stormed off the one time she talked to us about it, every other time has been with my dad with her often being attached on emails.

Finally, we moved to be close to them in an attempt it would finally give our kids a grandma in life and a mom in our lives. The day we moved in she made it clear she wasn't going to be free every weekend, and even left early on a vulnerable move day. That's another thing, when sister is struggling she says I'm so sorry! But for us it's quit you're complaining you'll be fine kid. She also has enabled my sisters bad choices in life. The ensuing few years were us constantly feeling like we were pulling teeth to get her to be in our life, they kept changing expectations of time despite plans and acting like we were asking too much. They went through periods where they gave more time like maybe 13 hours a week but they kept switching it, we had to keep pursuing it (it didn't come naturally like sister), and they acted like it was so much. She constantly gravitated toward adult focused time when we really wanted our kids to form those grandparent bonds, wanting things to be at our house, devaluing or dismissing our needs (saying we never needed a calm break in the house as homeschoolers and that they are supposed to watch the kids for dates outside of the house only, saying we could sleep downstairs at our house if the ac is out upstairs so they don't have to host us, etc). All we wanted is for our kids to get an inkling of a chance at building the bond that my sister and her kids naturally got given to them.

They dismiss our arguments now because my sister doesn't get as much time as we have gotten (because she doesn't have custody of her kids just every other weekend during school year and she doesn't live close), so our kids HAVE gotten more time than hers in the last few years since this happened, but that doesn't dismiss the attitude difference, lack of accountability for the past, or still feeling second rate (my mom is ramping up the time with my brother who i am close with now and love dearly him and his family and his kids who lives out of state more than my kids last year) but I'm just afraid it's going to continue to happen and be this way again with his family now or a shadow combined with whatever is still there with my sister in the way she talks and still prioritizes in many ways.. We said we need a schedule and equity. They say they will only engage now if they can be fully flexible like they are with "everyone else in their life", interchangeable with each other (when mom is the relational issue), and we will not bring up problems. Last summer was the climax after a year of estrangement from us to them (them just hanging with kids). They had lowered the time with our kids to 2x a month plus 3 2 or 3 hour solo times with my mom and the girls. But we had to chase these times and they weren't a priority in my moms schedule. She said she saw them "plenty". One of the times she ended up cancelling on us to go to my sisters (sore subject) and had no regard for the hurt it would cause (my dad was still willing to come). We confronted and we did get a little heated, as we have over the past few years out of desperation for them to see the pain and to have a deeper relationship. Full transparency we have said that they cannot continue to treat us as second rate, treat the girls as if they're not a priority, or treat us like our needs are unreasonable or we're asking them to raise the kids just by being actually involved. We have implied she is not a great grandma with bad priorities and we have distinctly said favoritism. My sister (completely out of conflict with us) ended up blocking my wife on social media, and my mom followed. They then sent us a 25 page email dismissing all of our claims and "accusations" and "attacks" and said the terms they will agree to. We responded by saying no, so our kids haven't seen them since last summer. It's so sad, I don't get how they could do this. But the whole family is like honing in on US, pressuring us, acting like it is US who can make the choice to just get over it and accept a non mutual relationship? It feels wrong , but are WE actually the wrong ones? We don't know what to do. They said they'd do a counselor but they're trying to have it be with THEIR pastor. Since the estrangement, my dad has said ridiculous things like that this is 100% our fault and we're keeping kids from them, that we should be grateful for anything given, that they'll go to my sister and brothers every weekend now if they want to, that we've gotten most of their time, that my wife is now affectively blocking my mom by not accepting her request after my mom blocked her, that nobody else has this problem with them, etc. My sister's friend sent my wife private messages cussing her out, extended family has unfollowed or deleted my wife on social media (I don't have social media), etc. Parents say what do they have to track how much they talk to siblings now too? Etc. tons of red herrings to avoid the issue. This isn't my wife, this is me, this is my family, and ultimately what we care about is our kids not being second rate their whole lives and being told to be grateful for that. How does everyone think what they've done to us is right? AITAH?