Enterprise inertia. Similar to Teams > Slack "because it comes with the Microsoft license or O365 tenant." Once an org grows beyond a certain size, vendor onboarding and management friction becomes real.
I really was just curious about any interesting gotchas anyone else has run into. Historically, Microsoft is a balance between "this is great because it's already here, we just need to turn on a button to enable it" and the quality or reliability being not what we expected, to put it mildly. That and onboarding is a headache for external tools, but is often a tiny fraction of long-term maintenance so isn't necessarily the highest-weighted issue.