> The paradox is that it was meant to avoid to write language support for each editor. Yet, if you want to support vscode you must create a specific extension for it and can't just have a language client.

On the one hand, this has always bugged me slightly. But on the other hand, every time when it came down to it in practice, I realized two things: first, a VSC extension that does nothing but wire up the LSP language clienting library is a tiny project with no major maintenance burden; and secondly, more importantly you usually want additional language-extension client-side features that are editor-specific by nature and either couldn't or shouldn't be abstracted-inside / covered-by the language-server / lang intel / IntelliSense realm. Syntax-coloring and other grammar-describing meta-data come to mind, or custom Notebook, or rich & productive build or debug or pkg-mgmt etc. helpers & tooling UX, etc. Stuff that arguably belongs in one's "language extension" but is mostly editor-specific and thus at the same time doesn't truly belong in one's "language intelligence serving".