"I can’t explain what lies behind human inaction on a topic as important as racism."
I can. Anti-racism is too much work for too little gain for those doing it. Outliers practice anti-racism. The rest may be persuaded to be inclusive, because inclusivity offers a plus-sum outcome, but it's no accident that BLM is a Marxist organization. Only Stalinesque coercion can get people to denounce their family, friends, and neighbors for every microaggression. At the end of the day, anti-racism is "to each according to his needs, from each according to his abilities" in a new bottle.
Even race mixing, which appears to be coming (think Barack Obama, Meghan Markle, and Derek Jeter), won't end class and/or caste. We will have castes until they aren't worth the elites' effort to maintain. Abundance and inclusivity are the solution. Lots of other things would be nice, but nothing else will actually work. Ending racism will be good for oppressed races as such, but ask the Dalit how being ethnically Indian has worked out for them.... https://www.britannica.com/topic/race-human/Indias-caste-system
Stable, viable societies honor saints, but they do not demand that people BE saints. Anti-racism asks too much, maybe not morally, but practically. We will have castes until they aren't worth the elites' effort to maintain. Abundance and inclusivity are the solution. Lots of other things would be nice, but nothing else will actually work.
"I refuse to accept these assumptions and conclusions about racism."
Is that the same thing as disagreeing? Or is it just Upton Sinclair in reverse, failure to understand something is true because so much depends on its being false? I understand when Ms. A. says she "need[s] to believe" in a better non-racist world. But needing to believe is its own counter-argument. If a question can have only one right answer, it's not really a question.
Refusing to accept facts is your privilege. Indeed, it's very American. 75 million Americans refused to accept that Donald Trump was a worse President than Joe Biden will be. Do you really want to pin your hopes on a country made up of such stuff practicing and responding to anti-racism?
We will "evolve" out of racism when it no longer confers a selective benefit. Anti-racism, which is a subset of cancel culture, just drives it underground, where it thrives quite nicely.