This is excellent. I've been searching for ways to use modern hardware with my Xournal/Xournal++ workflows, and this is a promising approach. I am, however, a little concerned about robustness of video streaming.
In an ideal world, Xournal++ would have a modern web-based front-end as opposed to GTK (which currently means it's de-facto Linux-only until GTK resolves issues with Windows pen/inking APIs).