I haven't tried it this week, but that was the first thing I encountered when my university switched us to Zoom. I could join by browser in Firefox and see screenshare and video, but I would have had to also dial in to hear audio via phone. In chromium, I could get audio and video together. But, it is a more limited interface than the native client in terms of seeing attendee information. This week, I also tried chromium and saw severe audio quality issues. Joining the same meeting with the native client worked much better.
I understand that our university is consolidating and it apparently works for large lectures etc. For my own use, with small technical groups, we were happy with bluejeans before. It worked by Firefox using just webrtc functionality, AFAIK. What I've read is that Zoom is doing their own streaming and codecs, not using browser webrtc functions.
As an aside, I also encountered sudden SSO login problems in Zoom this week on Fedora. They seem to be defaulting to an embedded qt5-webengine browser and this was not working right at all. Editing their config zoomus.conf file to turn off the embedded SSO browser was the only way I could get logged in again.
I think I'd prefer an extension to installing their client.
(Windows 10, if it matters. IIRC I had the same experience on linux)