>23 x 7 is split into ((10 * 7) * 2) + (3 * 7)
was the wrong way, then that is harmful. But if the purpose of the test was to see if you can do long multiplication, and you were not able to do it because you did not want to or like to do it that way, then that is a personal problem.
The reality is that school (non university level schooling) is not purely about education or exploring the 18 million different ways something can be right or wrong. It is also an exercise in navigating one's way around other humans and their expectations and playing the game that you will have to for the rest of your life.
There is also the constraint of limited budgets and schools having to make do with perhaps not the most qualified educators. And there is certainly lots of improvement to be made, but this "racist math" stuff seems to be counter productive.
> If we just tell that student their way is the wrong way, we risk turning them off to math for life.
I certainly disengaged from some subjects in school due to frustration with "thou shalt" methods of teaching. I was even removed from an upper level English language class because I didn't draw the same conclusions as the teacher from the material.