My point in mentioning screen was rather that despite having had solutions that work for decades, that everyone I collaborate with knows how to use, I can literally count the number of times I've felt a need to share just a terminal window with someone, rather than e.g. a full screen, on two hands over the course of 25 years.
It's rare enough for me to have a need for sharing a screen, but sharing a single type of window would cover just a tiny proportion of those rare cases.
My tech stack is atypical enough in many respects that maybe others will find it more useful, but to me this seems like a couple of useful but easily copied features (the auto-complete), and some stuff I'd never use.