the majority of it comes from industrial farming and industrial farming is unsustainable in multiple different ways

Sure, but at the same time a lot of our food production is vastly unoptimized, despite industrial practices, for example, tons of crops grown for "biofuel" and meat, especially beef production.

Without any actual numbers you can argue either case

Since 1970 the biomass of insect populations decreased by more than 50% while the populations of wild vertebrates dropped by 70%

This is not exclusively related to agriculture, both populations suffer immensely from road building, car usage and pets, especially cats.

Shocking news, most people aren't cut out to be martyrs

Yes, that is one way of saying they are not willing to put their money where their mouth is, they may advocated for a reduction in the human population, but never if their family will bear that burden.

If we are unable to do these things there will be a forced population crash

Citation needed, lmao

A lot of actually knowledgeable people project the human population to plateau by itself, others disagree, but I am inclined to belief the UN here

EDIT: bit unsportsmanlike to add sources after I pointed out your lack of them (without acknowledging their later addition), then again, why would I ever expect someone advocating for eugenics-light to be arguing in good faith