They have done it before. When the floor is dropping below the self-reliant bitcoin currency, then those who own more of it — and thus have more to lose — are shelling out more dollars to stop the bleeding. It worked so far, and in the process those few prime bitcoin holders increased their holding of the outstanding coins. Before this current dive 0.01% owned 27% of all the capitalization of the currency. A quick analysis points to the new figure of 32%. These very few still have the power to recover the currency, but every round it becomes more difficult. The one after next price drop will probably be too much for the frantic purchase to reverse course. Say then that bitcoin has a life expectancy of a year and a half. Smart money will pull out in time. Indications are that the big mining shops (10 top miners mine 95% of bitcoin) cancelled orders for new equipment, smelling the end of the sweet ride. 

Bitcoin innovation though, will outlast the current protocol. The brilliant ideas of a public ledger combined with public/private cryptography are the building blocks of the bitcoin replacement with better privacy protection (quantum safe), price stability, and smooth integration into legacy money: