I'll admit, I kinda skimmed through those controversial threads of K9Otaku's, in my replies to him I mostly just focused on his denial of how much genes affect everything and on his culture-first explanations of inceldom.
That said, if he believes in Ishtar as a deity and entity actually being that influential, rather than using "Ishtar worship" as his own overarching shorthand for the cultural forces behind feminism and so on, as I initially understood it, then this is a pretty good response to him. Why he thinks that a currently not-too-popular Goddess, as you pointed out, would be worshipped by elites and influencing them to manipulate the world in such a way, nevermind secretly pretending to be other Goddesses, is rather bizarre to me, and it's certainly not something anyone active in the modern occult sphere, such as yourself, would ever claim.