The definition I was stating has been standard in these discussions for decades. It is the second definition at Merriam-Webster:
https://www.merriam-webster.com/dictionary/racism
2a: a doctrine or political program based on the assumption of racism and designed to execute its principles
b: a political or social system founded on racism
The problem is, much like wildfires, racially distinct outcomes occur when there is no one trying to set a metaphorical fire. So, we still need a term for racially differentiated treatment from institutional policy that occurs without racially discriminatory intentions, the lexicographical equivalent of 'wildfire' in your metaphor.
Even your definitions make the point clear. It’s based on racism. Not it IS racism.
I’m open to new terminology. And I’m not arguing the massive impact power has on racism. I fully acknowledge it.