Same issue here!
Out of the blue, Microsoft Teams has decided to start pinning itself to my taskbar. I cannot remove it. I was given no consent over this change to my desktop. Right clicking does nothing - it's as if Microsoft doesn't want me to have the ability to remove it!!! Funny that.
I can't believe Microsoft still pulls these kinds of stunts. If Microsoft were someone you met at a bar, it'd be 5 minutes before you were so creeped out that you called the cops on them - they seem to constantly be making decisions on your behalf, about what's better for you, forcing things into your system that you don't want, and trying to charge you money for it while they're at it! It's like being 'software roofied'.
And this is coming from someone who spent about 30 hours trying to get Microsoft Teams work, out of a client requirement to use it for a project. Every bug imaginable was encountered by our team, who subsequently boycotted Teams. We went through multiple Microsoft support desks to try and fix the error that prevented any of us being able to log into the platform, and even then senior MS engineers didn't end up being able to fix the account issue. It wasted countless productivity, and here it is again, wasting even more time.
So the idea that the buggiest bit of software I have ever been forced to use, is now pinning itself non-consensually to my task bar, is just the world's hugest joke. It's like someone pinning up a picture of someone who's hurt you in your past, so you wake up each morning looking at it, and each time you take it off it's there again in the morning somehow.
What on Earth are you doing here Microsoft? Do you have any respect for humanity or are you going to just keep non-consensually trying to force buggy, hard to use software down peoples throats?
I'm sorry but after years and years and years of dealing with this in regards to Internet Explorer, Edge, and all the other terrible Microsoft applications that have tried to set themselves as defaults or force themself into UIs, I've had enough. This has to stop.