Totally true Jason. I've been living quietly with the Chats and the Teams smashed together under the Chats tab for a few weeks now, and it's been a horrible client experience. And the bug where the desktop app opens to the last chat is still there. For example: if I reply in a Teams Channel "chat" and close the app; and then open the app again; it will open to the last 1:1 personal Chat I was in and not the Team. So not only did they make the user experience worse/messier, it didn't actually fix the root problem.
Now we have an answer.. but in the form of an app update, not in the form of a reply.. the Teams interface has been updated to nonsensically smash the Chat and Teams tabs together into a tab now just called "Chats". Why would I want to go to Chats when I want to go to my Teams for completely different functionalities? You can't just throw stuff together and call it "streamlined". Another dumb update from Microsoft.
You can still separate them by going back to the old view or customizing the view.
However, this still does not address the problem of Teams opening to Chats and not having a way to change that.