I blame the political correctness industry for the deniers here. Clearly, the deniers were always given a hug and told what unique little snowflakes they were, and that all opinions, including their own idiot opinions, were equally valid. Nobody ever dared say to them "Damn, that's stupid", for fear it might damage their precious self-esteem.
And now we have them here. Self-esteem they have in plenty, so they proudly put their science failures on parade, unaware of how stupid it looks. And then it gets laughed at, because it's so stupid. A normal person would tough it out and take the criticism to heart, but deniers have been brought up differently. They are especially sensitive souls, so they'll respond to any criticism by wailing about being victims of a conspiracy.
And that's why I hate PC.