Well it is a good read and while I disagree with pos as the solution I do see that this is a real problem.
He talked about BCH I think his idea could be done but that bitmain would need to be in on a BCH attack since they have enough hashpower to defend the coin.
It certainly could be done with ETC vs ETH
Nice hash has
4400gh of hashpower for rent to mine ETC or ETH
https://www.nicehash.com/marketplace/daggerhashimotoETC has 6000gh to 11000gh
https://etcchain.com/chart/hashrateSo to attack some coins like BTG or ETC, you do not need ASIC.