It wasn't just crowd sizes being exaggerated. Sure, a sizable portion of the tens of thousands of lies and obfuscations Republicans (particularly the Trump administration) have told over the years that younger demographic have heard were silly nonsense with no direct harm implied or inflicted, but (a) there is definitely a cumulative effect and (b) many lies were much, much bigger: everything from COVID treatments to COVID dangers to climate change to surreal acclamations of authoritarians to denying election results and more. There's only so much an young, impressionable mind can take before it just says 'fuck it' and reflexive incredulity sets in.

I don't mean to downplay how troubling this level of Holocaust denial is. I'm just not sold that it is truly indicative of real data. After reading the article, I came away unsure about the methodology of the poll. In fact, I've been unable to find it anywhere. This line stuck out:
" Young Americans—or at least the subset of them who take part in surveys—appear to be remarkably ignorant about one of modern history’s greatest crimes. "

Based on this, I wonder how much this survey might suffer from nonresponse bias and possibly even bogus responses (I would count this as less likely that the former, though it's certainly possible).