Zoom operates a web server on your mac when you use it, and if you uninstall it, the server stays on your computer and is a security risk. Leo says he understands why it was designed that way, but having to keep it on your computer makes your computer a bot, and that's a bad thing. Zoom was also reporting your personal data to Facebook if you installed it on a mobile device. VERY BAD. When initially apprised on it, they didn't act right away. Now they're saying they have halted development to fix the problem. One thing they are doing is creating a "waiting room" for all callers.
Meanwhile, there's a phenomenon called "Zoom bombing," where hackers are breaking into Zoom meetings and acting like trolls.
Zoom is also routing video calls through Chinese servers, and although they claim they use end to end encryption, recently it was discovered that they don't.
Leo recommends JITSI.