When the existing whales are unable to influence bitcoin prices like before, they are likely to jump to the altcoins because they don't have to counter short sellers there.
Reddit's / r / btc community took the API breadcrumb as a signal that both narrowed Bitcoin Cash's looming Coinbase timeline and provided evidence that Coinbase intended to add trade options for the currency — a significant sign of adoption that would surely influence the altcoin's price across exchanges.