Navigating my family’s kids

My niece 6yrs and nephew 8yrs and their parents drive me insane. My partner and I are choosing to be childfree, but that doesn’t mean we dislike kids. I actually enjoy being around kids for the most part and was excited to have a nice and nephew by marrying into the family. Unfortunately, time spent around them and the parents bring out so much negativity in myself. Every time I am around them I walk away aggravated, feeling sad about my own childhood, and questioning how they’re being raised. To me, the parents do permissive parenting within the guise of gentle parenting. The kids have no responsibilities or chores, do not greet guests including myself and their own family members even after we’ve said hello, have no challenges in life besides begging mom and dad for what they want and seeing how long it takes for them to give in. They want for nothing and the level of spoiled makes me sick. Adult conversations are impossible because the kids constantly interrupt with bs and the parents just stop whatever convo and leave it for the kids. The kids are constantly over scheduled because they want to do all these sports and parents cannot say no. They have no manners. They are still bed wetting at nighttime and sleeping with parents. I want the kids to stop being so scared of everything, to have time to imagine and learn how to do things for themselves, create things, learn that the world doesn’t revolve around them and how to navigate that and not be stifled by being put on this pedestal by everyone. It is not helping them! I play with them when we’re together and try to let them do tasks independently, not just do it for them like they’re used to. I wanted to over the summer take them out just my hubby and I and do the fun adventurous things we like to do (beach, boats, surf) but do not feel comfortable even asking for my hubby and I to take them out on our own because they always have some obligation and it’ll just be a shutdown anyway or they won’t want to be away from mommy and daddy. The grandparents say nothing and enable it all which also drives me nuts because where I come from, your grandparents call out bad behavior. My hubby isn’t bothered by this but I can’t take it!!! I want to be around family and not be so annoyed and critical etc. I am married into a completely different family than what I know and trying to get used to it is so hard. Since we won’t be having kids and there’s no other kids in both of our families, I’m saddened to not have a great relationship with my niece and nephew. How do I reframe this whole situation? I tell myself, they’re not your kids, not your problem or just wait until they are older and are horrible humans. But I still cannot use these reframes to get over it!