a consequence of thinking cultural relativism is true is that you must admit that they were correct in the attitudes they held
No, and that’s stupid.
Let me clarify, because I want to make sure you understand. I’m not saying that I have a different take. I’m not saying that perhaps you misunderstand. I’m saying that’s a fundamentally stupid thing to believe.
The whole point of relativism is that your simplistic concept of ANYTHING being “correct” is wrong. It’s relative. It’s not correct. Nothing is correct. Some people just thought it was correct.
Relativism says there is no objective truth but you’re just for some reason trying to say that relativism believes in objective truth but only for supporting bad things. It’s a ridiculous, childish take on a philosophy and I’m having trouble understanding how you could come to that conclusion. It has the intellectual rigor of “I am rubber you are glue”.