The frustration doesn't come from AAA titles being shit. It comes from AAA titles often being safe, derivative, predictable, and homogenous. Buying an obscure game you were told is strictly average and finding out it's strictly average is fine for most people, even if it does nothing new or particularly interesting. Buying a game that took hundreds of people several years and hundreds of millions of dollars to make and received a massive advertising campaign, unstoppable word of mouth, and promises to shift the entire medium forever... and finding out it's strictly average and does nothing new or particularly interesting? That makes people cross.
The disconnect between expectation and result will always color our judgment, and that's not a bad thing, because when we get surprised by good work from unlikely places, they deserve that extra praise for doing more with less, and without the odds stacked in their favor. AAA titles, by contrast, have every conceivable advantage and time and time again they waste this churning out the gaming equivalent of plain white rice because they can totally get away with it. The urge to see these games' developers punished for this irresponsible, arrogant, and short-sighted behavior is completely justified; if they are going to go through the trouble of raising the bar for themselves, they should be expected to clear that bar, not to be congratulated for blowing ten times the effort and still doing no better than anyone else.