After 9...Qxf6 the move 10.Qd3! creates quite a few problems for Black. The main threat is Bxb7 plus Qb5+, so Black has to waste a move on ...a6, and fall back in development.
See how easily the young and promising IM/WGM was caught in a very bad position, and lost quickly:
I think this particular case can be generalized under certain French lines that I mentioned (most notably 1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.Bg5 dxe4 5.Nxe4 Be7 6.Bxf6 gxf6!).
It's also a matter of choosing between two evils in this case.