People are different. Some see leaving home, flatshares, travelling abroad, etc. as independence. Some see setting up their own business or focusing on education to get a good job or even marriage and family as independence. Everyone's different.
My sister lived at home till she married and then again a bit after, then they bought their own house together and had a family. Both she and her husband had, and still do, a great social life, but were very mature, sensible types who really wanted a home and family.
They were 27 when that happened and are now in their late 40s and perfectly well-adjusted. They didn't want to live together before marriage, it went against their beliefs.
Her elder daughter is very similar. She goes out, has plenty of friends, but is quite religious and business/career-orientated and is fine living at home, paying rent and working in the home, too. She doesn't want to rent from a landlord and all it entails, and my sister and her husband are fine with that.
Horses for courses.