Are there even any good isekai anime? They all seem tasteless and disgraceful wish fulfilment with zero actual examination of its own premise. I suppose anime like Spirited Away and Inayusha are technically isekai, but obviously when anyone says Isekai it is more a modern Japanese young person being transported into a RPG setting, so the genre is more about nondescript young adult deep in alienation exercising power and agency over others in the most generic euro-fantasy with absolutely no self-awareness whatsoever.
It's not even that you can't make a story out of power bringing worst out of someone or circumstances driving people into exercising their agency to harm of others or even the simple idea of how people can do bad with good intentions, no. It's just they have slaves and a harem of girls while they had nothing back in their "old" life, that's all. Even character development as much as it exists seems to just come down to them moving past insecurity and inaction to become a go-getter in a way that reminds of hustle culture except fantasy.