In my workplace we use zoom breakout rooms as an alternative. When we have a meeting we move to the main room and have it there. Otherwise each member is in a breakout room.
Exactly. If I want to drop in all I need to do is to check the breakout rooms list then move to the room where my colleague is. And once done I can go back to my breakout room.
We also use it when pair programming remotely. It's quite effective and it eliminates communication barrier.