Stop nitpicking this. There's nothing unclear or ambiguous about 'less'. It refers to a smaller quantity of something. There's no reason not to use it. This is just pointless grammar Nazism.
Debating grammar is perhaps one of the best ways to actually learn grammar and otherwise sharpen language skills. I don't think it's a coincidence that grammar and language discourse has been a past time of the learned for millennia around the world.
Not interested in weighing in on less/fewer, but not sure architects of genocide is the comparison we want for grammar sticklers, even if it's become a common turn of phrase. Cheapens the real thing, doesn't it?