I recently participated in C++ on Sea (https://cpponsea.uk/) - online, of course. The conference setup used https://remo.co/conference/ which automatically groups people into tables, where each table is essentially a video conference call. You can move around freely between tables but each table can only hold 8 people.

I felt it was possibly better than a physical conference because it's so simple to join new conversations - no walking around looking for interesting groups (you can see who is currently sitting at each table) and none of the nonverbal social awkwardness in joining a conversation. Plus you always have the names and profiles right there. Never been easier to meet people imo.

I'd contradict your claim based on this experience. You clearly can establish small groups, and it seems to work really well when you do.

Agree, but that’s better than nothing. I spent several months working with a remote team. I didn’t really know my teammates for six lonely months, they were just names in a screen, until we started scheduling social meetings. Of course it’s nothing like the real thing, but it helps.

"the biggest problem being that you cannot establish smaller groups"

Zoon has breakout rooms.

Rally.video has tables.

In my dnd group I just switch Discord channels when we need synchro conversations when the group is split. Because as DM you sort of have to participate everywhere this is harder but I like the multi-channel method.

I wonder how much time and effort has gone into solving the hallway effect. Or the cocktail party effect.

Maybe we just assume it can't be solved but haven't really tried that hard, or at least that recently?