> Emacs already supports asynchronous I/O and has sentinels for exactly that. However, not everything that runs on Emacs is taking advantage of that functionality. It is therefore up to you, to use the proper package (or not use the wrong one)

>Finally for LSP, I always recommend Eglot over LSP Mode

As far as I can tell, Eglot also just blocks waiting for the server response.

Unfortunately, that is the current state of the emacs package ecosystem. Org mode freezes emacs. Magit freezes emacs. Most package writers just don't bother writing their packages with asynchronous I/O in mind. There is no point blaming the user.