> bad encounters with Zoom, previous cases where Zoom has dismissed or downplayed an exploit, etc.
Have they?
Their disclosure policy [1] sounds reasonable and their public response [2] to the recent accusations has been text book, if you ask me. They even hired top industry experts (Alex Stamos, Matthew Green, etc.) and acquired keybase to strengthen their security.
To me it looks like Zoom got lots of attention at once, and thus had lots of security issues at once, that would not be out of the ordinary if they had been more spread out. However, them lying to their customers about E2EE is hard to forgive.