Using Teams with multiple organizations

Tech_Dad_Tom, you absolutely can now add multiple orgs (not even limited to 2). Microsoft removed this limitation quite a while ago (in 2023, I believe, but not certain on exact timing). To do it:

1. Click your account icon in the upper right -- title bar, just to the left of the minimize button
2. Click on "Add another account"
3. Specify your tenant email address (can also add a personal account to use in Teams Personal, but that's a different system that has been supported for several years)
4. Then, whenever you want to switch between them, just go to that same account icon and select the account you want to use

This was one of my biggest complaints with Teams until they added this. Teams is so much better and more capable now than any of the other similar options. It combines the best of Slack, Zoom, OneDrive, Outlook (minus email), Skype Phone Calling (VoIP), SMS/MMS text messaging, SharePoint all into one easy-to-use app. It does far more than any of the alternatives, while remaining just as easy or easier to use.

It still has issues for sure, and I post my feedback for improvements frequently (e.g., Planner doesn't allow pasting screen captures or images into comments, when making a phone call from Teams it always opens the window to almost fill the screen and doesn't remember my resize, and a few other minor annoyances). But relative to the competition? There is none. 

The last big problem with Teams for me (other than the Planner issue noted above, which is really more of a Planner problem) was the difficulty external parties had joining recurring Teams meetings, but Microsoft fixed that late in 2024 too.