Failing to engage with ideas you find distasteful just creates a vacuum of good information; which is the environment where conspiracy theories thrive. I've followed Graham Hancock for twenty years and have yet to see anyone properly dismantle his positions. I don't believe everything he says: but dogmatically dismissing him only fuels his narrative that mainstream archaeologists are trying to suppress him in order to save their jobs (and grants).
Given the highly falsifiable nature of his claims it should easy enough to disprove them. That nobody chooses to do so is quite curious. I can watch a hundred spirited debates and proofs on both sides of flat-earth, fake moon landing, essential oils curing cancer, and evolution vs young-earth creationism. What is so special about archaeology that it needn't mount a similar, vigorous defense?