It's delayed more than it could have been if they did initiate it though, that's the point. If they told me what they wanted I might be able to answer/action it when I get to that message, instead of having to wait for a future message to find out what they need.
I think you misunderstand, it's not about speaking up IN the meeting. It's about the conversations that happen AFTER the meeting, that are facilitated by physical proximity when exiting a meeting.
That's exactly what I want.
I feel like I'm not getting my point across, the point is I may not be in a position to respond. I'm chairing a meeting, sharing my screen, or heck maybe just actually paying attention in a meeting rather than sat there staring at chat software, I'm not going to switch focus and say "hold on everyone, someone just asked me how my day is going, give me 30s to respond to them...". It's the equivalent of answering a phonecall in a meeting, complete no-no IMHO.
Maybe it's more a expectations thing, some people think of messages as some sort of ice breaker ship that should be allowed to smash past whatever a person is dealing with and engage them immediately, I view it as just another task that needs addressing when I'm able to. If it's that urgent at least tell me what it is you need!