If somebody has X or Wayland and a DE on top of it, why would s/he want to use vim? Why not just use one of the editors that come w/ the DE?
Because vim has super-powerful features for development. I still prefer it to any IDE I've ever used over the past 30 years. (Although I will say that VS Code is better for read-only browsing of large code bases. Other than that use, I find its behavior to be infuriating, and its "vim mode" is crap.)
vim is also superior to nano-type editors for any nontrivial editing of non-code files, with macros and powerful commands that can reorganize thousands of lines instantly. Notepad++ is also OK for that work, but you have to install it separately and is mostly just for Windows.
BTW, with a desktop environment, use the GUI-based gvim, not plain vim in a terminal. You get scrollbars, better cursor and mouse behavior, etc.