The interface exists. It’s up to zoom to support it. Why are you under the impression there is a technical issue? THERE IS NONE.
It’s up to Zoom to support the aforementioned interface.
Wayland’s display handling in this manner is for security, the user will be shown a permission request dialogue to let the app access the screen only if you permit it, it’s also disallowed from accessing anything except what you’ve given it permission to. This is not even a new concept, just not doable under X.
It’s also possible to create the lawless model of X under Wayland through a protocol if you desire to make one, but it makes little sense to throw away this better model just for the sake of some shitty proprietary apps who don’t care for Linux anyways