I think it's an extension of the popular opinion that MAMEdevs are all really stupid and we've sort of "duh"ed ourselves through ~7000 romsets by some combination of theft and pure luck. Especially that Aaron guy.
as well as the atari/midway hardwares no one else tried to emulate, cps2 encryption and neogeo rewritten emulation (with all the flickering hardware originally had and other emus never showed)
there will always be people which do not believe to the facts, so don't bother
more on topic, I really like these progresses on DSF... kudos to all of you involved