The thing is Emacs, just like Lisp, can incorporate all those neat ideas without drastically transforming itself. I don’t know any strong features other editors have that users can’t replicate unless powered by closed source code. It won’t be as polished, but that mostly because users have different workflow.
Yup, Lisp is extremely malleable and egalitarian and unrestricted - that's why there's almost universally at least one dialect of Lisp exists for any non-lispy language and almost every known programming paradigm.
The only rule it insists on is the parentheses, and it's quite ridiculous how people dismiss the entirety of this foundation for incredibly powerful ideas and abstractions, solely for that reason.
There's nothing wrong with looking at the ecosystem and saying "huh, this is a pretty good idea". Emacs (the community as a whole) didn't ignore the LSP, and thanks to that it gets first-class support for tools that otherwise would have required someone to show up and "do the work" to get it to happen.
I do think we're in agreement about "strategically, not tactically". Like Emacs _is_ doing its own thing. It's just that sometimes you can see good ideas from other places.