The subtext is that if you don't find those ideas extremely appealing, it must be because you're not sufficiently acquainted with them.

Just like the missionary / evangelist

Look, that's straight up stolen from Evangelical "theology". The people who aren't "saved" just haven't learned enough about it. That's part of why "witnessing" is such a big part of their religious practice, on the off chance that their particular story is the knowledge you need.

It goes hand in hand with their belief that progressive values are performative and insincere. Thus their fixation on false flag operations.

This was a part of the brainwashing hysteria post-Korean war, too. A number of PoWs wanted to remain in Korea, rather than return to the US, and the conclusion was they'd obviously been brainwashed because nobody in their right mind would ever be a communist.

My parents tried this exact thing on me with green beans. Didn't work for them either.

Is it the small government idea? No Is it the low taxes idea? No Is it the strong national defense idea? No Which one exactly are we talking about? You know the one

This is exactly in line with their religious beliefs about proselytizing. It can't possibly be you understand exactly what they're offering and find it lacking/unhelpfull/downright awful, it's that you just don't [whiny voice] understand it fully. I understand, thought about and soundly reject it

"You just haven't had good sushi."

Same as the idea that people get more conservative as they get older, which of course implies that if you’re left wing you are in fact simply immature

Had a libertarian coworker who simply refused to believe that I’d actually read Atlas Shrugged and still thought it was bunk.