Ishida come across to me as an incredibly weak willed person who is prone to extremism. You see this phenotype fairly often, anyone familiar with TNO may remember the mod's creator, Pink Panzer, claiming he was a Stormfront poster before being converted to socialism by Vaush vids.
People like this will often convert to new beliefs as they feel the tides shift in some way, but it's always to some insane radical version, not the real political drift that can happen to a person over time.
Ishida is probably the most extreme example, starts fairly edgy and apolitical, mostly a centrist nose-tweaker trying to mock everyone. Then goes radfem, but specifically sex-negative radfem (the sort that would mutate into the TERFs as the troons rose up), which had not been the in vogue version of feminism since the 80s at the latest, let alone when he decided to join the team. Then he gradually starts talking more and more about troons, before eventually breaking entirely and switching off into rad trad esoteric pagan nazism, abandoning any of the leftie pretenses of his radfem period.
Sidenote: Trying to uphold hellenic pagan greece as some kind of ideal society of beautiful, clean, pure people is hilarious on so many levels. Not even getting into how sexual and graphically violent their mythology was, there was the pederasty present in some of the city states as well, not exactly the lovely trad society that he envisions.
The Greeks also got trashed by the Romans, who were also pagans, not the Jews imposing Christianity on them.