I found Webex to be quite a lot worse than Zoom in my limited experience. I attended a few IEEE presentations hosted on the platform. Audio didn't connect smoothly and needed a few restarts. The talk was constantly interrupted by a chiming noise whenever a person joined or left the meeting. I remember finding a configuration setting for this but the hosts didn't see my message (another bad feature), as this was a meeting-wide setting rather than a client one. Even if it were configurable per-user, that chime turned on is an unexpected and intrusive default setting.

Beyond that, I couldn't see the presented content in full-screen. There was a lot of junk in the form of perpetual UI elements for the "fullscreen mode".

These seemed like pretty fundamental misses for the platform to make.