To me this highlights how backwards our way of building software is.

Having a user display and draw on top of an image is trivial, and something our systems have been able to do for decades.

Streaming video bidirectionally is also trivial and well supported by our primitives at this point, even though it's merely a decade or two old rather than almost half a century.

And yet, if you want to combine these two very primitive operations, you need to find the app that supports exactly the use case you want (not guaranteed), or to be a developer yourself.

We're still catching up to Engelbart's demos, and it's disheartening.