Many of us still can't afford housing anywhere near where the jobs are. How could we possibly put down roots and be a real part of a lasting community worth investing time, effort, and possibly savings in?
What if you can afford the housing but don't want what you can afford? How many immigrant families lived in 2 bedroom apartments in brooklyn while working in the city?
That's also part of it. The generation before me, 3 brothers bought houses in the same cul de sac. The chance of any 3 siblings being able to do that anywhere in the US nowadays is extremely slim. Home prices have gone out of whack with wages. On a side note another reason we have less friends is that we work far longer hours than generations before us did. We are the most overworked generation in history, strangely enough...
You don’t need that at all. I’ve seen people temporarily renting in a location act as better community members than someone who has owned a home for 10 years.
Dorms are a poor example. Everyone there expects it to be a temporary community other than larger structures like fraternal organizations that slowly nibble in new members and continuously digest them as things progress.
It's not like you're in an apartment or house where you don't know if it'll be next year, 4-5 years, or 10 years when you move; only that someone's going to raise the rent, or you'll get a different job somewhere far enough away and have to endure the hardship of moving everything yet again.
Do you expect it to be commonplace that someone who starts living in a college dorm will still be there in 10 years? I hope they'd graduate by then, and failing that it seems likely they'd run out of debt to continue funding education.
Meanwhile, 'the golden days' of the American Dream included a stable house that lasted most of an adult's life, and maybe moving again at retirement. It also included a career track at a corporation that continued to pay well as an employee developed into a more valuable 'resource'. (back before Human Resources wasn't as transparently about harvesting all the value they could...)