These traditions developed around families with children.

The situation now is that divorce and childlessness are common and people are adapting accordingly.

Personally, I think it's sad. Long-distance relationships don't work. Yet, as I see it, short-distance relationships do work, though a period of adjustment may be required.

Medium-distance relationships are stuck in the middle!

And, to put a cynical hat on for a moment, the powers-that-be may be just fine with this. They want people isolated in separate dwellings for purposes of taxation, property pricing, general conformity to their agendas, etc.