I despise LaTeX for two reasons: It's offensively inelegant, and there's no such thing as "LaTeX".
The offensively inelegant point is purely a matter of taste so I won't belabor it. The second point means that every author writes their document with their own particular suite of LaTeX add-ons, and if you don't have all of them you have no hope of compiling the document. There's Joe's LaTeX and Sally's LaTeX and Jennifer's LaTeX but nobody uses "vanilla LaTeX." So even after I download "LaTeX" (which is itself multiple gigabytes in size), I still have very little hope of compiling documentation that comes in LaTeX form. I hate LaTeX with the heat of a thousand suns and I'm embarrassed for my profession when I find it still in use.
The one thing LaTeX does well is math; if I had to write math papers I'd probably force myself to learn it, but fortunately I don't.
I tend to use org-mode for everything now. I don't use markdown because it has the same problem as LaTeX: There's really no such thing as "markdown" and the vanilla Daring Fireball version isn't facile enough for real work.