I thunk the oldest Millennials are the last group of people who got online when it was possible to be forgotten and to start again in a new space without too much effort. Being able to try something out and discard it if it doesn't work is an important part of gathering maturity online and off-line, and it's becoming increasingly difficult to do that in both spheres.

I don't believe age segregation is the solution, but I do think there has to be a way for them to build a space that is theirs and curate who gets invited inside, so they can really call it their space.