automated high frequency trading also does the important work of eliminating the question "Which exchange should I buy AAPL at?"

HFT is mostly ultra-fast arbitrage programs, and the benefit of using them far outweighs the downsides.

Maybe the problem is not with HFT but in the industry as a whole

A human trader can also cause the entire market to crash because of one mistake. See Waddell trading 75k e-minis or PVM trading 7 million barrels of brent while drunk.