LSP changed the game. For me in python I used to use jupyter notebooks and elpy to get a similar experience to what I now get with a LSP, but LSP gives you more. Everyone is catching to LSPs. You can say the VSCode is a electron hog, but LSP was an amazing development, and you have to thank Microsoft (yikes) for that.
I know emacs is lisp almost all the way down. But except for a few hardcore lispers and distros mantainers, most users only make plugins or simple functions to give emacs more IDE features. The core-with-plugins is old but most software and editors are not build in that way. It is what got me to use emacs. I used some IDEs before that and they were bloated as hell. The model is good and emacs is a extreme example of it.
I am guilty. Sometimes you want to know what the hype is all about.
But I never got into Sublime. It was as slow as vscode, but my compute was less powerful then. And it was not free software. But you are right, Sublime is an example of the core+plugins model. It is just that now even vim is going in that direction.