Yes, whilst there are some girls too these days, (who stay at their parents home for many years,) when I was growing up, boys/men never left home until they found a woman/a wife/a partner. And if they didn't find one, (or one who wanted to live with them/married them,) they would stay with their parents. And the mum waited on them hand and foot. The longer time went on/the older they got, the lower the chances were of them getting a woman!!!
And yes indeed, some were still with mum and dad in their 50s and 60s. Then when the parents died, the man inherited the house, or the tenancy. Some councils didn't let 'children' inherit, and wouldn't let a single male occupy a 3-bed house, but they would allocate them a 1-bed flat (or a small bungalow if they were over 65, and/or had a disability.) Then a sister, or an aunt, or a female cousin would 'help' them with housework, cooking, washing, and life admin. They were NEVER independent.
Girls/young women (including myself) left home and got their own place. (Often by early 20s.) With a friend, or on their own. Or they'd go work on a cruise ship, or work at a holiday camp, or work abroad in bars and hotels whilst travelling. I couldn't wait to leave home, and left at 19, and moved to a big city, where I did temp office work, learned new skills, travelled with friends I made, and learned life skills/how to budget and fend for myself. (Yes, some girls/young women went straight from their parents to getting married/living with a man, but some did go it alone for some years...)
I moved back 'home' at 23, (after 4 years,) and stayed til I was 24.5. I met DH at 23.5, and moved in with him a year after dating. Never went back. DH had lived with his parents til he moved in with me (he was 25.) If he hadn't met me, he very likely would not have moved out til his 30s, if at all. (Unless he had met another woman!) He was very close to his mum, and she spoilt him rotten, and he was hard work to start with, and expected me to be his mummy. He learnt fast!!!
.