Arc has this feature, which is quite useful when presenting.
It would be nice to have PiP when switching away from google meets meeting. For Arc, it pops into a separate window with custom controls for google meets, and I imagine that's a custom integration. I'd be fine with a resizable PIP window showing the current meeting.
Attaching Arc's impl (with my pic blocked out)
other nice things arc does is when you're presenting a tab, it highlights which tab is being presented, and allows you to hover over a different tab and present that instead. all very nice, but as stated above, would be fine with a simple pip to start.
