In college I was talking with someone from Japan who said he grew up in a house with his parents and grandparents.
Essentially, how it worked in his home, was that the kids stay with their parents (and, in his case, his grandmother as well) until they find a partner to move in with, with one child who agrees to stay with the parents (and grandmother) for the purposes of looking after them, even after finding a partner.
The parents (and grandmother) were smart enough to know to give privacy, leave the home for a few hours for meals, shopping, etc.
Then, when the kids are born, the grandparents (and great grandmother) are there to help look after and raise them (no need for baby sitters, no need for daycare, etc.). Cousins would also be dropped off to be looked after if needed.
Grandparents were smart enough to go out with the kids at times to give the parents privacy.
This system makes it easier to raise children, makes it easier to look after the elderly in the family, etc.
That doesn't mean I don't think that you should move out if you and your parents don't get along (like you said, if someone is gay with homophobic parents), but in a functioning family, I genuinely think that this system is better. One of the big advantages is that it doesn't dehumanize the elderly as much as what happens in western countries that just put the elderly in retirement homes.
It saves money, creates a stronger family bond, increases empathy for the elderly in children, etc.