There is an alternative people have used before discord came, it is called teamspeak. Is still around as well, but works more like a federated system since everyone has to set up and host their own server for people to use.

There is another, semi official linux client called vesktop. Comes with a range of plugin options, all improving or enabling functions the default client doesnt offer or hides behind a paywall. It also has had screen share on Linux for the longest time,if you do the switch give it a go. Certainly better than the default app