He is always saying price has to follow hashrate/difficulty. But that is completely wrong.
Hasrate follows price!!
If price goes down significantly over longer period of time, miners will shut down some of their mining hardware, therefore hashrate decreases and difficulty goes down.
If price later goes up again, miners will switch on these mining hardware again cause it's getting more profitable again, therefore hasrate increases and difficulty goes up. This is Bitcoin mining 101!
Good point. Hashrate must follow the price. This is why the miners don't decide the fork, the market ultimately decides the fork. The miners would need to have 100% hashrate while the other chain has 0% hashrate so the market would be frozen, but that never happens, on every split there's always some hashrate on the other end to set a market.
This is why segwit2x will fall again, just like BCash.