Why would I want to use Teams on Linux? One reason to use Linux is to avoid such bloatware with unbearably poor UX. Rumor has it that a usability consultant died from a heart attack when he saw the first alpha build, but I may misremember the story (or confuse it with the deadly joke by Monty Python). I'm totally fine with text-based chat, and it had better be implementing an open standard (e.g. USENET news or Jabber…
I do count “running commercial software” as a need of mine. I would not be using Linux if I couldn’t run Windows games on Steam, 1Password, Slack, Discord, etc.
Nobody’s forcing you to install Teams, and someone out there is breathing a sigh of relief because they have another option besides Mac and Windows for running the programs they need to run.
I’m not really in a race to be the most opinionated user on the planet who refuses to use an app with a … or + menu, I just want a good OS that runs any program I might need.