> What is the best sweet spot an editor/IDE has achieved to date?

Unironically, maybe VS Code.

Everything simple you can do with it, either comes built-in, or within Github/Microsoft ecosystem, or has an official plugin that gets recommended and featured by the editor itself. Plugins from individual hobbyist developers I have, I can almost count in one hand. (VSCodeVim being the most important one)

Now I compare this to my Neovim setup, and that one is basically running on charity from OSS developers.

I can't even start listing the issues with your hasty generalization here - I see outdated anecdotal evidence, survivorship bias, vague metrics, false correlation, goalposts moving. While your personal experience likely genuine, presenting it as evidence that Emacs is inherently impractical as an IDE only adds to the fallacy of generalizing from a single data point to universal truth.

I have completely opposite experience with [modern] Emacs. Of course, it wasn't smooth from the day one, but neither was my ride with different IDEs. Somehow, I keep coming back to Emacs because no IDE ever provided all the machinery I need to be productive. For me (and I suppose for many other people), Emacs is far more sweeter spot of an IDE than any other alternative.

Emacs has eglot built in these days and it works quite well as an IDE

An emacs "distribution" like e.g. doom-emacs has worked to be quite stable for me.