I've been looking for this exact question, but can't find it or at least one that I think works. I would like to set up Zoom audio so that it does not suppress other microphones when one person is talking, or, at least allows as much sound as possible without feedback (ideally without headphones - but maybe it's only possible with headphones).
You might wonder why since it goes against the "one person speaking at a time" approach of a typical meeting. But some applications are: for people to be able to responsively read text together (like in a liturgy or drama), or to sing together, or simply to allow more natural noise to happen when the main person is talking. It's quite unnatural feeling to hear complete silence in a classroom. However, you also don't want the main speaker to get interrupted every time someone coughs or knocks their mic.
The best I've found is to:
Set Suppress background noise to "Low"
enable "High fidelity music mode"
turn off "echo cancellation"
Am I missing anything? Thoughts for anyone else who has tried any of the applications above?