Zoom app on Apple TV 4K?

No. Only iPhone, iPad and the iMessages applet.

Contact the developers of Zoom if you would like to see a version for the Apple TV.

https://support.zoom.com/hc/en?_ga=2.241094403.1860256584.1700151895-64964249.1700151895

does not sound like zoom made one, but then it's pretty new that it gotten a facetime app

not sure if apple allow third party apps access to use an iphone as webcam which is required for the facetime app to work

AppleTV (2nd Generation) and Zoom App - Apple Community