My company just started requiring Microsoft Intune Company Portal app to use Teams and Outlook. From a friend in IT infosec at another company said the app can push apps, require certain settings, password requirements, or OSs, and can see a lot of stuff on your phone. I don't think this level of intrusion into my personal phone is warranted or ethical. Be warned. I'm just going to uninstall and suffer the internal political consequences.
One thing to note (for what it's worth I use Island rather than Shelter, but the end result is the same), Microsoft can't get their shit together. While most things work normally with "Work Profile" apps, a couple of things don't.
The biggest annoyance by far for me is I cannot answer Teams calls on Android Auto. Perversely, I can reply to messages (DMs or group chats, but not channels) hands-free by talking to the car, but if a call comes in the UI only appears on the phone and not the car's display.
I'm sure Microsoft could fix this, but it's been broken for the ~2 years since they started supporting Android Auto in any capacity, so I'm guessing they aren't going to.
Overall though, my favourite feature has to be the one-click toggle that disables all of the work apps. No notifications, no syncing in the background, no nothing. As soon as my phone connects to my home WiFi, an automation turns it off for me. Glorious, glorious silence.