Everytime I am on some damn webex with people yelling into their conference room speakerphones, I just want to hang up.
Compared to Slack we have fewer problems with people dropping out of calls or losing audio or video and audio and video quality are generally better. Screen sharing is better quality and less buggy and let's you share individual windows. For calls with people outside the team we have fewer problems connecting than with Skype or Google Hangouts. It handles people calling in by phone or from mobile devices with poor connections more robustly. Overall no real revolutionary features, just consistently good execution.
Linux desktop adoption may not be great, but many good software engineers use it for work. In our team it's hard to find a windows laptop. Zoom is the only software that works for us.