You make good points.
But you can’t think in anything but language, so everything proceeds from that. What can’t be said must remain silent. Culture can’t be made from nothing. It has to be thought into being. Language allows that thought. Below language is only instinct, which is fine if you are a migrating bird, but not if you want to build a space shuttle or write a novel.
All of the abuses you mentioned are true. More literature doesn’t necessarily prove anything, but it can’t just be dismissed out of hand. IQ is so discredited that it makes a bad example. What is true now may not be true in 50 years. There was a time when everyone knew the earth was flat. It was true, until it wasn’t.
And, of course, as part of the feedback loop, language is also a tool, a powerful one that can be used for good or evil. We see much struggle to control people by warping and shaping language, on both sides, the PC SJWs vs the alt.right. Both groups know the power of controlling language to censor free thought and stifle individual liberty. And both groups are doing their best to have it their way.
I’ll admit I don’t know what an Asian is. I don’t think I can know that, at least not in English. On ther other hand, I’m not sure what a Canadian is either. Hmm… :)