I tried them a bit and often they can infer immense amount of ideas from the immediate source context and suggest paragraph patches semantically close to what I had in mind from just one word.

Saying this as a vi/emacs user who liked to automate via macros, snippets, dynamic overlay inserts and what not.. I still enjoy being sharp on a keyboard and navigating source / branches swiftly but LLM can match and go beyond it seems. (not promoting them, feel free to stay in good old vi command sequences if that's fun for you)