I have also tried ein-mode, and sometimes use it. I haven't used it enough to have a super educated opinion but it didn't blow me away.
I don't think it supports cell folding (?) as an example missing feature
Minor point but it also can't/shouldn't support widgets, which we use at work. Any extension to jupyter is going to be written in javascript so there's an element I'd be locking myself out of the ecosystem.
I didn't mean this as a criticism of emacs, my post said that the best thing I know is emacs, just that it's (probably) not the future of editors imo so I'm reluctant to throw 100 hours into it.
> I don't think it supports cell folding (?) as an example missing feature
If I understand what you mean correctly, that would be handled by built-in outline-minor-mode, or by a third-party Emacs module like yafolding or fold-this.el. Emacs packages tend to be made to compose well with other packages (it's a requirement given how everyone's Emacs is a special snowflake, unlike any other Emacs).
As for widgets/Jupyter extensions, then yes. Emacs can't really help you there AFAIK.
I don't think it supports cell folding (?) as an example missing feature
Minor point but it also can't/shouldn't support widgets, which we use at work. Any extension to jupyter is going to be written in javascript so there's an element I'd be locking myself out of the ecosystem.
I didn't mean this as a criticism of emacs, my post said that the best thing I know is emacs, just that it's (probably) not the future of editors imo so I'm reluctant to throw 100 hours into it.