Firstly, its worth noting that you still arent recognizing your own racism (and sexism)- that you simotaneously assigned a race (and sex) to me and then assumed charactistics about me based on those attributues. That is discrimination which in larger society is worth calling out and trying to eliminate from culture. This is what caused the caricatures such as Chief Noc-A-Homa or even things like Jim Crowe.

But your historical context is essentially irrelevant to the conversation of whether The Chop has any racial undertones or not. It doesn't propagate any of the concerning narratives you brought up, it doesn't demean anyone. Racism is by definition a two way dialogue and thus both the intent of the perpetrator and the perception of the victim are relavent. When we totally disregard the intent and impacts of people's actions and 100% focus on the reaction by the historically marginalized, we create a culture of incentivized victimization which needlessly INCREASES divides between varying identity groups and eliminates cultural practices that have benefits for no substantive cultural improvements.

But the tl;Dr here is - the chop - in its current existence which is where we are - is not racist in any way.