There are other girl drummers that place their tom(s) at such an extreme angle, such as Torry Castellano of The Donnas. I am pretty sure they do that because it makes getting around the drums on fills less demanding for them, and allows them to keep their hands close in without reaching out too much. Women are built differently than we are and the drums are a very demanding instrument. Whatever they can do to make it less strenuous for them on the road is their goal. Not that this matters, but I talked to Torry at this years NAMM show, and my goodness she is hot in person.
And yes.... Jack White does write the drum parts for Meg and he is a very good drummer himself. She plays the parts he writes for her exactly, so that in itself makes her a talented drummer. Who knows how good she is just sitting down and playing for fun? Charlie Watts, Stan Lynch (ex- Tom Petty) and Phil Rudd (AC/DC) are all very simplistic drummers on recordings, but all of them can really impress with their chops outside of their band restraints. Same goes for Neil Schon, the guitarist for Journey. He is very restrained and follows the melody of what is written -- but outside of Journey the guy has world-class chops and can flat out shred ala Yngwie Malmsteen. My point is that it is unfair to judge someone in the context of what they play in their "famous" band gig, and to say someone is not a great musician based solely on that is ludicrous at best.