To be clear, aside from the part I quoted, I agreed with everything else in your post and thought it was an interesting take, but again I have to take issue with this:

as far as I’m aware, they don’t carry the clinical state-sponsored efficiency that is a hallmark of the Holocaust.

I'm not going to analyze every single atrocity since 1945, but the Cambodian genocide was certainly state-sponsored, efficient, and horrific:

"20,000 people passed through the Security Prison 21, one of the 196 prisons the Khmer Rouge operated,[4][28] and only seven adults survived.[29]"

"The executed were buried in mass graves. In order to save ammunition, the executions were often carried out using poison or improvised weapons such as sharpened bamboo sticks, hammers, machetes and axes.[6] ... In some cases the children and infants of adult victims were killed by having their heads bashed against the trunks of Chankiri trees, and then were thrown into the pits alongside their parents. The rationale was "to stop them growing up and taking revenge for their parents' deaths."

"People were imprisoned and tortured merely on suspicion of opposing the regime or because other prisoners gave their names under torture. Whole families (including women and children) ended up in prisons and were tortured because the Khmer Rouge feared that if they did not do this, their intended victims' relatives would seek revenge. Pol Pot said, "if you want to kill the grass, you also have to kill the roots".[169]"

"There are many accounts of torture in both the Security Prison 21 records and the documents of the trial; as told by the survivor Bou Meng in his book (written by Huy Vannak), tortures were so atrocious and heinous that the prisoners tried in every way to commit suicide, even using spoons, and their hands were constantly tied behind their back to prevent them from committing suicide "

"all medical experiments were systematically conducted without proper anesthetics.[173] A medic who worked inside S-21 said that a 17-year-old girl had her throat slit and her abdomen pierced before being beaten and put into water for an entire night. This procedure was repeated many times and carried out without anesthetics.[174] In a hospital of Kampong Cham province, child medics cut out the intestines of a living non-consenting person and joined their ends to study the healing process. The patient died after three days due to the "operation".[173]"

"Twenty-six-year-old John D. Dewhirst, a British tourist, was one of the youngest foreigners to die in the prison.[17] He was sailing with his New Zealand companion, Kerry Hamill, and their Canadian friend Stuart Glass when their boat drifted into Cambodian territory and was intercepted by Khmer patrol boats on August 13, 1978. Glass was killed during the arrest, while Dewhirst and Hamill were captured, blindfolded, and taken to shore. Both were executed after having been tortured for several months at Tuol Sleng. Witnesses reported that a foreigner was burned alive; initially, it was suggested that this might have been John Dewhirst, but a survivor would later identify Kerry Hamill as the victim of this particular act of brutality."

https://en.wikipedia.org/wiki/Cambodian_genocide

https://en.wikipedia.org/wiki/Tuol_Sleng_Genocide_Museum

https://en.wikipedia.org/wiki/Killing_Fields