Not really with widely available general purpose hw.
If the total mining reward is $100k per day someone with that amount of money can set up a pool and buy it by paying that money in return for the POW in whatever form it is in.
I agree that it is not a good attack, it is expensive and seems criminal from the outside, and does not ultimately give the ability to bend the coin in a desired direction.
Also, using general purpose hw is inherently more decentralized, enabling small scale mining which would make pulling off something like that successfully a lot harder.
General Purpose Hardware is by default more decentralized due to there not being monopolies or barriers to entry. This is a side point, but do you favor BCH changing the mining Algo?
The bch community looks at the algo change just like how the useful idiots of Coretards looked at the capacity increase back then. We'll see where this attitude leads...
Changing the algo is not conceivable for BCH. Getting consensus would be impossible. (context: Just fixing the DAA reads like a civil war story.) Build better faster on new turf.