This isn't your argument. It is your claim. And I see nothing that you have posted that supports the claim.
That people have used a scientific theory to promote a false narrative that some groups of people are inferior humans does not demonstrate that the theory is bad. It demonstrates that those people are grasping at any reason to support racism.
You could argue that people are acting badly by using hammers to beat on other people, but that doesn't make hammers inherently flawed. It only shows the flaws of those that use them for selfish, malignant purpose.
Ultimately, your claim and the narrative that follows it are a poorly constructed and fallacious attack on something you don't really seem to understand. My conclusion is that your rejection is based solely on the conflict of the science with your personal interpretation of scripture. It has nothing to do with any valid dissection and assessment of the theory and the evidence it explains. That would be an example of the poor reasoning you keep claiming to be here to thwart.