Since you asked nicely I'll respond, the modlog already says it well enough:

inappropriate. talking over / arguing with a marginalized person about their lived experience.

Basically OP picked up on a (relatively inoffensive) stereotype that's consistent with the way that east Asian people are essentialized in western news media, you came in being like wtf are you talking about (understandable), they gave what I thought was a reasonable explanation but instead of you know, absorbing it and trying to see it from their point of view you doubled down and decided to argue with them, questioned their literacy and (ironically) made them out to be ignorant.

Thing is, words have denotative and connotative meaning and they were describing connotations. Other people picked up on those connotations right away so that should tell you it's a learning opportunity rather than a reason to lecture someone, the way you argued with them was indistinguishable (imo) from crypto-racist dickheads arguing in bad faith, but judging by how you've followed up I've gathered it's in good faith. Idk dude, I hope this helps because it seems like a blind spot and I don't mean that unkindly.

Best possible explanation I can give while at work, but hope that all made sense. Peace comrade.