They left Linux users in limbo, while Zoom worked for everyone.
They couldn't handle more than a couple of people in a call.
They also had Lync which was rebranded as Skype, so you also had other bad software masquerading as Skype which wouldn't have helped their image.
You couldn't share a meeting URL and have the call in a browser for the longest time.
They only started to try again after Zoom picked up being the default word for video calls.
But really, much of Teams was built upon Skype, and that is the dominant market player by a long shot.
Do you have any source on that?
https://twitter.com/Carnage4Life/status/1558054445237149697?...
The graph doesn't include Zoom or Google Meet, so is not a perfect representation.
That's when I switched away.