What are the go-to subjects for revealing the true, regressive beliefs of reactionaries who don't consider themselves reactionary? Off the top of my head:
-Trans people in sports: Major gateway to transphobia and misogyny. Complaints about trans athletes inevitably lead to sexism towards literally any woman with muscles. Pretty sure this is how Joe Rogan and a ton of his supporters became so unhinged.
-Affirmative action: So, so many liberals and "leftists" will complain about how they would've totally gotten into Harvard and Yale if not for The Blacks^tm^. Love to bring up SAT scores even though they've been proven to be racist and classist and a shit metric for intellectual value.
-Shakespeare authorship question: A bit niche. Basically, Curtis Yarvin and other Dark Enlightenment dweebs don't think that Shakespeare was capable of penning such timeless plays because he wasn't rich, and according to them, not rich=dumb and uncreative mental husk.
As someone who works in "STEM" (don't like the term but using for clarity): Ask their opinion on subjects that are not STEM. If someone is cool, the worst thing they'll say is along the lines of "I'm bad at geopolitics" or "I hated studying history in high school". Reactionaries however are filled with blind rage for humanities classes and will go on a rant about how they are useles useless and a waste of govermnent money to teach art at public universities and other shit.
Justin Roiland level chuds will say not only are the humanities useless but that the humanities can be fully automated with bazinga tech (unlike geniuses like themselves!).