AITAH for making a "soft move out deadline" a hard one?

Looking for a sanity check here, or to find out if I'm actually an AH.

Context: BIL is going thru a divorce and he and his ex are sharing their marital home every other week. Ex SIL has an apartment for her "off" weeks. BIL lives in our (me, 45 F and my wife 60 F) basement rec room for his off weeks. So far, this has been ongoing for 1.5 years. At first, we didn't put a limit on it. "As long as you need," we said. After it became apparent that it's...a lot having someone in our space, we had a talk where he agreed to figure out something else by next Spring, 2026.

BIL is great. He's nice, relatively neat, and overall a great person. I genuinely like him and enjoy his company. The issue is that our house is small and the rec room was one of the main reasons we purchased it. It's the space we use for gatherings, crafts, and general messy fun that we don't want in the main living space. To disclose fully, my wife didn't much care about this space but I LOVE IT. It was almost the entire reason I wanted this house.

Since BIL moved in, it is a massive pain in the ass to host anything, or really DO anything, down there. We have to move his stuff, clear the fridge, refill our beers and whatnot into the fridge, and then undo/clean it all immediately when we're done so the space is "his" again. He is also there every Sunday, either coming or going, and I am a die hard football fan and love to host my pals here for games. Since he moved in, we have hosted exactly twice. It's just not comfortable to do it anymore since it's technically someone's large bedroom now.

There are minor issues, like he's messier than us so his cleanups have to be re-done (especially if we want to actually use the space during his home weeks). He overloads the washer, doesn't contribute financially, and his ever-increasing amount of stuff is making our storage spaces crammed. I asked my wife SIX TIMES if he could please bring his enormous kayak home so it wasn't laying in our yard. There's only a half bath down there so he uses our shower. I can't just be naked temporarily in my own home when he's around. We all share the duty of taking care of MIL with dementia so "his days" become "our days" because he's at our house.

Little things, sure, but they are adding up into me feeling pushed out of my own house. If I'm honest, I suspect my wife would want him to stay as long as he wanted. I do not. I want this to end by Spring, as we casually discussed, and I want it to be a hard deadline and not flexible. I want my house back. I want my wife to back me up on this but at this point I'm ready to address it head on myself.

AITAH for pushing for a hard-line move-out deadline?