More info. FaceTime in Monterey (now Beta 4) is absolutely maddening. Not only does the Full Screen menu option not work, but now the maximize/minimize buttons don't work either. There is a right click Zoom option, which goes to "sorta full screen" but not true full screen. I don't know what they are doing with the application, but is simply is not working as expected and the usual options are there but non-functional. There is something weird going on. I thought it was something about the 2019 16" MBP, but I've replicated the problem on a second computer - a 2019 iMac 5K. This is definitely a bug.

Strangely, according to dozens of sites, the 14.7 GM was supposed to be available today 9/16. Stranger still, the build number for 14.7 GM is the same as the 14.7 RC released several weeks ago. Yet, there is no indication that 14.7 exists on the update channel. Anyone know what is going on?