After many years, the sad truth is that wysywig editors are only as useful as the output generated when users copy and paste from word documents, which is what I have found the vast majority of input from actual end users to be.
Not supporting wysywig is a tactical advantage in my book.
So not supporting pasting from Word at all, and then forcing Word users to learn something like markdown (no easy feat for the average computer user) is better than supporting pasting from Word in most cases, and letting them edit with a UI that they're familiar with?
I've gone the markdown route in the past, but recently also put a WYSIWYG editor in a project. The client was insanely happy that he and his employees didn't have to deal with teaching/learning markdown and converting Word documents to markdown anymore. Pasting just worked.
Not supporting wysywig is a tactical advantage in my book.