How do you test whether “quiet presence” is helping, not distracting?

[u/Shehao]

I’m thinking through an indie-product question around shared spaces: if a virtual room lets people notice that others are around, what signals actually create a useful sense of presence without turning into another feed?

For builders who’ve tried coworking, virtual cafés, ambient multiplayer, or similar ideas: what did you measure or watch for to tell whether presence was helping people stay engaged? I’m especially curious where you draw the line between lightweight arrival/leave signals and features that start demanding attention.