However, their insane ad revenue keeps the boat afloat, and allows them to fund moonshots and failures. Yahoo doesn't have that insane revenue stream so that strategy didn't work out so well there. Am I missing something?
That quote about "throwing rocks" in the article is misleading - Google has done exactly that and succeeded. Their trick is that they're standing in a quarry and don't have to give a damn how many rocks miss as long as they get the occasional hit. Mayer carried over that philosophy to a company with half a dozen rocks and nowhere to get more.
It's telling that Mayer never really revealed a 'plan' for Yahoo ('content' and 'advertising' don't count). She bought a bunch of things, tried a bunch of deals, and clearly expected value to shake out somewhere like it does for Google. But Yahoo doesn't have the time, revenue, or infrastructure to slot in a stream of experiments and wait for a win - their only attributes were staff and users, and they needed to consciously turn that into money. It's closer to Facebook's monetization task than Google's, and regardless of her talent Mayer's background was an impediment to what needed to happen.
That management style does not fly at a company that has no real product or revenue and is struggling to become profitable.
Most "normal" companies just do not have the luxury of withstanding a huge margin of error on cost vs benefit.