A change of POW will only result in a new race.
but whoever takes up that new race will be fully aware that they'll be kicked to the kerb if they wilfully go against the interests of the majority bitcoin users. if it happens once, it can happen again and they'd better know that.
all they'll have to do is check the smoking ruins that were the chinese cartels.
So they will be more ruthless and try to gain a bigger profit while they can. Destroying Bitcoin in the process. Maybe they also would try to hide it better to have a longer run.