Not all of us fell into that trap! My dissertation was written almost entirely using a default document class and a handful of packages, and only towards the end did I apply the university document style to come into compliance. I had more than enough to do on the subject of the PhD and didn’t have the patience to burn time on typesetting or fiddling with macros.

I’ve found in the decades since then that my most productive co-authors have been the ones who don’t think about typesetting and just use the basics. The ones who obsess over things like tikz or fancy macros for things like source layout and such: they get annoying fast.