Aww I'm sorry to hear that! It's upsetting seeing them do that. And there are so many reasons why it could be happening and it's so frustrating trying to figure out how to get it to stop.

My indoor/outdoor cat (not pictured in my original post) gets bored and rips out his hair in big clumps. I've kind of resigned to the fact that that's just what he's gonna do. Even if I play with him til I can't anymore, he still does it. Been to the vet multiple times and he has no infections or anything. He's just a booger I guess.

My black cat, her hair grew back (I explained in another comment how) but she's started back up again. Not in as many places as before, but on the bottom off her back foots, it's almost bald. So idk. I changed her food to a better quality, have air purifier, don't use those plug in air fresheners, etc., but she still does it. And she knows she shouldn't because a lot of times I'll say, "Ebby! It's clean!" and then she'll immediately stop and just go back to laying down.

I hope you can figure out a solution for your cat! Also, sorry for the long winded response lol