I have been trying to educate myself about the topic recently, though, and would strongly recommend looking into some of the excellent work on systemic racism in the US if you’re interested in learning more.
The documentary “13th” (available for free on YouTube at the moment), the 2nd season of the podcast Scene On Radio (“Seeing White”), and the book How to Be An Anti-Racist are three things I can recommend based on what I’ve read/heard from them so far.
What you’re calling the “recent forced redefinition of racism” is not especially recent. I first heard this argument around 30 years ago, and at the time dismissed it, but now understand why people want to emphasize that over the definition I recall learning as a child which was structured along the lines of a belief in superiority of one group over another.
Having a belief may impact how you feel towards someone and how you act towards them, and may even have an impact on that person if you are in a position to influence the course of their life.
Having a system that is designed and reinforced to encourage disparate outcomes is far more impactful to that group as a whole.
I’m not going to argue that both aren’t harmful, but I’ve certainly come around to the conclusion that systematic or policy-based racism (if you’re uncomfortable calling it racism, feel free to disregard the name and come up with something you’re more comfortable with) has disproportionately affected Black and non-black people of color in the US.