It makes me laugh all the “rules” people are putting on it being “ok”. What business is it of yours anyway? I mean I know OP asked the question so people are answering, but ultimately other people’s living arrangements are nothing to do with anyone else. I find all the judgement a bit sad.
My DD is 30 and is at home. In her early 20s she lived in a “crappy bed sit” and became so depressed she was suicidal. So of course I had her back home. When she was 25 she moved in with her partner. He became abusive over time. So when she felt able to leave him, again there was no question, she could come back home.
DS is 31. He has ASD. Despite his difficulties he landed a job abroad. It was covid that put an end to that. So he’s back at home too. He isn’t interested in a relationship. So he couldn’t care less if women won’t date him because he’s living at home!
They will both probably move out again at some stage but I don’t really care when. They cook for themselves, do their own washing, pay their way, chip in with chores. We live like it’s a house share. I stopped being “mum” a long time ago in that regard. It’s also pretty handy to have DS around when I need to move heavy furniture! Financially it makes sense for all 3 of us.
I was forced to leave home at 16 and as a result made some pretty poor choices and really suffered with my MH. The one thing I was adamant about with my own DC was that as long as I was alive they’d have a roof over their head if they needed it.