Does RST have a WYSIWYG editor? Linter that auto-corrects mistakes? Last time I looked neither of these existed. I have a bunch of rst docs that I want to to large edits on, and doing so has been so painful I've decided to migrate to markdown even though it's not as feature rich.

Not much in the way of WYSIWYG, unfortunately. There've been some VSCode extensions in the past to simplify editing but that's about as good as it gets.