For starters, it's closed source, centralized and proprietary. You have no control over your data and the product's future.

What's right with teams? Every time I open that miserable app I want to deep fry my computer

MS Teams is designed to create siloed teams and organizations. It discourages public chat and collaboration. It encourages private group chats.

I refuse to believe this isn't a bait comment. Given that there aren't any humans who like Teams, this is either a joke or you're an alien.

It's the singular worst piece of software I've ever used.

everything?

It should be pretty easy to list one thing then, like the fact that Teams doesn't cook bacon.