I agree with these, though the pandemic showed us (at least in my scenarios) online meetins really suck for a lot of the softer, agenda-less type activities. Casual, in-person hangs become AA meetings. It felt like we were sitting around a church basement on metal chairs (with the crappy coffee IRL too) waiting for our turn to speak. One of the good things IME was that scrum or dev-sized teams adopted extended pairing and group sessions; I saw (some) people get a lot better at working in public and sharing knowledge at this level.

The OP mentions it at the start, but I will reinforce: meetings suck if you're not prepared; use them to do work (like brain storm or make decisions) not share information. Breaking the "meeting as the big reveal" habit is surprisingly hard, but also solves the "should I attend?" question. To your point #2 a lot of that can be solved without attending if the appropriate prep and follow-up is covered. I don't really like RACI charts, but they do provide some value as a looser guide to thinking through the 2 questions you raise in point 2 above.