Is the reason that he wants it administered by "good white people" because every other ethnic group (including the "bad white people") is nakedly self-interested when it comes to racial preference?
As to why Kendi supports it, who knows. Lots of people attach a low price to their dignity.
Is that worse than not picking a single Hispanic, Muslim, or Asian because they are Hispanic, Muslim, and Asian?
The main flaw in your blend of anti-affirmative action argument is that at it's core it's a pro-racism argument, which supports the racist status quo as a default desirable scenario by first going out of your way to reject each and any alternative to the racist status quo.
Systems like this have historically been managed by the dominant "white people", which have unknowingly or not been advancing "white people" almost exclusively whether due to good or bad intentions, thus forming a vicious cycle. See for instance companies that employed machine learning models to drive admissions which ended up admitting candidates which already match the candidates which were already admitted in the past (white candidates from specific white-dominated academic institutions) and rejecting everyone else in the process regardless of ability.