And, of course, manual labour takes more time than mechanised labour, thus reducing time that might otherwise be available for questioning why the tractors were Leapbacked to begin with.

I admire that attitude, really. Well, you might find them to be of interest because in both cases, you're dealing with governments that attempted to phase out modernity and what they saw as decadence. The case of Cambodia is particularly horrifying—among many, many other terrible things, "intellectuals" were rounded up and worked to death and executed wholesale, and simply being able to speak another language or wearing glasses was sufficient to count one as an "intellectual".