Yes, I believe that every person who is able to work and make money should live on his own, build his own life and raise family. As long as young people stay living with their parents after maturity they are postponing their responsibilities and acting immature. The moment a person reaches his maturity and gains legal right to work and live on his own he should leave the comfort of his parents' home.
People should move out on their own when they are ready. Otherwise they are setting themselves up for a life of poverty and borrowing money from their parents for the rest of their life. Living with their parents until they are more established helps both the children and the parents.
Young British adults shouldn't be pressured to move out sooner simply for the sake of moving out sooner. Most of them probably don't want to live with their parents forever. However, moving out too early can mean they end up exhausting their savings or getting in debt because they weren't properly prepared. It's better to move out when you are on solid financial footing, even if that takes longer than what some random person feels is acceptable.
While it's not good to live at home with your parents for years and years, it is okay for young adults to seek the sanctuary of living at home for a few years after they get out of college. Most parents welcome it, and it saves the young adult the expense of paying rent or taking out a mortgage too early in life.
Young British adults should not be forced to move out when they are ready, whilst it is true that 'young adults' should move out of their parents/guardians house before they get to being a full adult (by full adult I mean before they get to age 25 or something) putting unnecessary stress on them to move out before they are financially or mentally ready would be damaging to their mental health.
(OWN OPINION, NOT NECESSARILY TRUE)