You bringing sex into the debate, your accusations of sexism and this point toward you being the sexist, if anyone is. She is CEO. She is almost entirely responsible and accountable for company strategy and performance.
Mayer has proven herself through the ranks of many prestigious technology companies throughout her career, but her performance as CEO has been an embarrassing disaster.
You have a funny definition of "many". She's worked at exactly two tech companies in her career: Google and Yahoo. For such a shrill critic of her performance, you're remarkably uninformed about what she's accomplished.
Oh boy, here we go.
Hmmm, to me and everyone I know, Yahoo! Mail is where you send all the trash and unwanted spam. It's surprisingly common practice, and my perception of Yahoo! hasn't changed a bit.
Short memory, short career or just sexist? In less than 2 years at Yahoo, Mayer brought in unprecedented leadership in a byzantine group left unmanaged for years.
Doesn't Ballmer beat her wildly in being lucky/overrated 2001 to 2011? Remember the disastrous yahoo buy out in 2008? Talk of being lucky that it failed. Or Blackberry?
Mayer turned around Yahoo's perception and fixed key products. She pointed out a talent and reputation issue and tried to solve that (http://qz.com/184046/yahoo-says-marissa-mayer-has-fixed-its-...) - should Yahoo just have done and bought nothing because of increasing valuations?
There's no actual point to ad hom like this. Yahoo's strategy is not solely Mayer's. It may not be working, you can disagree with it, it's plain populist to single out Mayer.