Earlier quoted context omitted.
See my comment above. LSP servers are complicated beasts coming with a lot of specific dependencies. It is simply impossible to ship all available language servers together with Emacs. Even VSCode does not do it. For popular languages it downloads them automatically for you. But this is exactly what "lsp-mode" (the alternative to "eglot.el") does, too [1]. If you are an expert in a specific language it also should no…
Yes it can be set up, but my point was precisely that it(LSP servers for popular languages) is not baked into Emacs, instead making them complicated external dependencies necessary to be set up to get a basic IDE functionality of code completion working. Code completion works out of the box for example in IntelliJ for example without needing to download and install further packages. The tree sitter approach does soun…
Emacs has LSP client that works will all LSP servers. It's your responsibility to bring an LSP server or implement your own, not Emacs'.