You're right, they are debatable.
My article is outlining why I encourage everyone to narrowly-define "systemic racism" juxtaposed alongside of "social racism" or "cultural racism."
I know people want to act as though sociologists, community organizers, and political actors suddenly have some undisputable moral authority over this issue because they are attempting to universally change the definition of racism. They don't. If you and Mrs. C. can't understand why someone finds it offensive to dismiss a racially-motivated physical assault as "prejudice," then there's no hope for you.
"Power + Prejudice" is what sets apart "systemic racism" and makes it systemic. Therefore, it only follows that there are alternate forms of racism that are NOT systemic in nature.
I'm honestly mind-boggled as to why people view this as an unreasonable position. Well, actually, on second thought -- no, I suspect I know exactly why they are embracing this coy sleight-of-hand. But that is an extrapolated and tangential discussion.