CMC is not enough to make good trading decisions anyway. So a good trader should not just rely on CMC but should do deeper research and analysis themselves.
Currently, I only trust the top exchanges that are chosen by people because these are exchanges with large trading volumes and can liquid at any time if you want.
Even top exchanges have trading bots that can be used to pad their volumes. All you can do is analyze which pairs have enough real people trading to offset the trades of bots.