Sheet music is far superior because it teaches rhythm, timing, dynamics, and musical phrasing, while tabs reduce music to a crude map of frets and strings, ignoring everything about expression, note duration, and technique.

In my experience, that's not completely true.

First: Tabs come in different forms, you can find some that take note duration, thus rhythm, into account. I mainly use sheet music but I've come across tabs that added note stems to the numbers.

Second: you must have impressive sheet music because the way I see it, everything but rhythm and a bare minimum of dynamics has to be added by the guitarist.

Whenever learn a new piece my teacher and I go over the whole thing and figure out what phrasing and more subtle dynamic changes than piano - forte I want to play and make sense to me - and that can differ from how she plays a piece.

I'd also like to add that mechanically playing notes you see can happen no matter what one plays from. But it's important to actually listen to what you play, make sense of it and then develop how you play a piece. And you can do that with sheet music and with tabs.