Ideally I'd like to be able to have multiple editors open to the same session. Shared buffers (files), shared registers, but ability to have different views of the session too, in different shapes.

Maybe I want a main editor view in one virtual desktop, but a different editor on the same session on the side of a screen showing off a bunch of documentation, to compare against.

Or I'd like to be away from home & open a web editor, without changing the editor at home. Or maybe I want to let a friend attach their editor & have a shared session we can pair across.

I think it's a mistake to bucket neovim as a terminal program. That is one modality you can use to access a headless program. But it's far from the only one. And the whole point of having a client server architecture, to me, screams not only about the decoupling, but also implies a >1 client capability. Neovim allows this, it's just not very good, since everyone's client has to share a row x column configuration.