For whatever reason 6.1 Sol is completely lobotomized for me this morning, so it wasn't helping much with the investigation, but it was pretty clear that MSFT was having issues.
I have a teams app with Outlook integration and received a bunch of 502s to smba.trafficmanager.net and a my logs are riddled with "RestError Temporary connection issue when contacting service. Please wait before retrying request"
I will say this, having apps deployed on Slack and Teams, Slack rarely has issues (an exponential backoff is enough to simply never worry about my Slack integration). With Teams I have mysterious failures to debug at least 2x a year - and they're often not very transparent about them (often my first instinct is to search Twitter and find people complaining about the same thing).