So would the use-case mostly be for people who edit lots of files over shells? I guess I was mostly thinking of coding stuff. Or do people use it for coding too?
Of course vi/Vim is used for programming ('coding').
I've been doing that since the early nineties. First vi, later Vim.
I like it better than Visual Studio, better than Eclipse and way better than VScode.
I mostly use IDEs for day to day coding, and pretty much every IDE supports vim keybindings, which I always have enabled. I also use vim in the terminal for small edits and one-off files, so it's not either/or.
After the initial learning curve and fiddling with settings, it just becomes natural and you can edit code or other text at blazing fast speeds. I also find that it helps with RSI by reducing arm motions reaching for the mouse.
Of course, there are other good options out there, but if vim fits your brain, it can significantly boost your editing speed. For those who say programmers don't spend that much time typing, that's true sometimes, but there are periods after the design/planning phase where we type a lot, and I want that to go as fast as possible while I have an implementation loaded into short term memory.
As someone who used to be a vim skeptic myself, I'd suggest you either give it another look or just accept that it works well for other people and go on with your day.