"Would it make [an object of ridicule] if I did the same?"
No, of course not. This is a different issue. It has to do with lazy kids who live off of their parents' charity. Most do not pay rent. Personally, I think they need an ultimatum from their old man, just like I got (ie: pay rent or scram). Keeping the family together under one roof for business or health reasons is a different ballgame.
You are absolutely right. Victorian young marrieds lived with their parents. This notion that you are supposed to be economically independent in your 20's only made sense if you got a good union factory job after high school.
If you are in college and saddled with debt until your 30's failure to launch is just plain the norm.
I graduated from High School in 1978 and I and EVERY SINGLE ONE of my friends moved out of the house that summer. And 80% of us went to college (working our way through in service jobs).
Of course, those were the days when it was "If you want to live under my roof, you follow my rules!" So we all said "OK, we don't want to follow your rules anymore."