I'm in one nonprofit org using MS 365 and Teams, and listening to the guy behind the original decision talk about that ecosystem, I think its popularity really does come from propaganda. I was almost convinced until I actually used it... what a piece of junk. It's ugly for me and borderline unusable for our nontechnical users. I'm in charge now and considering ditching it.

The only saving grace is that members who can't deal with it are using local MS Office, which has some integrations with 365, thus making it kinda viable. But I feel like it's still a net negative.