I wrote my thesis in LaTeX, which is very unusual for my discipline. Now that I’m done with that, everything we’re doing it’s collaborative Word docs. Collaboration features in 365 have been transformative. (Remembering the dark old days of emailing the Word doc around like a hot potato.)
I’m very used to Word and can get it to do some great stuff that most people don’t even know about, but I wouldn’t touch it for something over 20,000 words.
As for LaTeX, I was fine once I got a good template going. Writing one sentence per line is a fantastic way to draft. But there are some fine tuning things that I remember took up a lot of time that I would have had no problem fixing in Word. I distinctly remember trying to get tables to look right when you had paragraphs or dot points in cells.
Oh, and that one reference whose URL refused to break in the line and instead just went off the page. I never found a fix for that.