Did you misunderstand? That's niftynei's text and she's not criticizing PoW, the point is that MEV is harder to achieve in a standard bitcoin-style PoW based "election" of next block producer, compared with something centralized or simple round robin etc.

(Iirc this is a problem they try to address in some proof of stake algos - if anyone can see in advance which party will be the next block producer, it leads to undesirable outcomes.)