I use Teams from Chrome&Firefox on Linux without a teams account. I've attended 100s of US State government agency meetings this way, for many years.
https://support.microsoft.com/en-us/office/join-a-microsoft-...
So this means that I pull my customers into a competitor product, and they also get to hear me badmouth Teams if I find an opportunity to do so.
Teams doesn't have to be better, they're just bundled.
It's better than where we were (Cisco jabber) but also worse than what's out there.
Absolutely a monopoly maneuver.
and didn't really maintain for at least the last 2 years either
(it basically ran a often very outdated version of the web app + some AFIK unnecessary and buggy custom audio handling)
Do you maybe only do calls through Chrome? Or maybe you have a user agent spoofing extension (or similar) installed in Firefox?