I agree, it’s always struck me as an oxymoron. Though I do wonder when theists say this if the hate all the other deities? It’s a bizarre rationale tbh.
Often in debates with theists some of their claims are countered with examples from the bible or koran, but of course this is only used “for the sake of argument” to demonstrate the contradiction in their reasoning.
My thinking precisely, if any extant deity could be demonstrated with sufficient objective evidence, I’d cease to be an atheist, but that wouldn’t make me worship it, or become an adherent of any religion. Those are two entirely separate and distinct lines of reasoning.
I know (s)Hitler was real, but that doesn’t make me a fan.