I set up a special account on my Mac, found one other coworker who's used and likes Emacs (but doesn't main it at work), and did a little experiment involving us both logging into the account and using emacsclient to connect to a running Emacs instance.

It worked rather well. Bit of setup hassle and it's stinking insecure, but not too bad on those fronts even compared to the VSCode solution.

But Emacs lost. All the developer effort is behind VSCode and the IDEs now. So if you want a robust, supported solution for this kind of thing, you have to leave Emacs behind.