The bitcoin price is set via supply and demand in the market, I think it can deviate a lot from hashrate. If someone is willing to pay $20,000 for a BTC, then that's the price, and then miners will follow the price or not, usually they will because they don't want to be sitting upon their ASIC machines doing nothing. It's yet to be seen too for how long miners keep juggling with their hashrate from BCash to Bitcoin back and forth too, or if any other real competition in the SHA256 realm happens. Im not worried about this tho, I think the mining industry will keep following the price as it goes higher and new players will enter the market (non chinese).