I was pretty explicit about the intuitive background of my position, and request for anything except a just-so story. Your article already accommodates another explanation than power, so we have already moved to a better understanding than you or the OP expressed. And I certainly acknowledge that it challenges my intuition; clearly power and anger are important motivations that I wasn't really considering. However, I don't think the article or what I've now been reading really support that "almost all rapoe is about power and not sexual gratification."
This thesis provides a broader survey and importantly when it talks about rape and power, it talks about power rape used to "conquer and sexually dominate" the victim. That to me says there is a key element of sexual gratification at play, because sexual domination is itself about sexual gratification.
The other aspect the author surveys that hasn't come up yet is hostility towards women as a key predictive factor. We know from the whole incel phenomenon that a key factor in men becoming hostile towards women is in difficulty finding a sexual partner, so this is a whole side to the story which, simmering below it, has sexual gratification as an important influence.
And I still don't understand how rape through the use of date rape drugs can truly be an expression of anger, or a means of exerting power: these rapes are often intended to remain secret from the victim, so cannot be used in that way. I worry that there's a tendency when throwing out these sweeping generalisations to ignore high numbers of rape enabled by drink and drugs
So, you've certainly helped evolve my view on this, but I don't agree with the original statement still.