This argument makes literally zero sense. The fact is that your claim is objectively false. I wishlisted the game on Epic because it looks interesting, then found the itch.io page when looking for more information. Arguing "but it's part of the game" doesn't negate that you're listing this as a feature, not an in-game story element. You're telling people that this is the first game with dark mode, and that isn't true. It is very definitely and without any ambiguity, a false statement you're using to market the game. And in most parts of the world, false advertising is illegal, so you should really consider stopping doing that just from the fact that you've admitted to knowing it's false, rather than waiting for the platform you're selling the game on to call you out on it.