Part of it's getting dog piled when they try and have a discussion, but part of it is also that the NeoGAF rules make a lot of the social conservative beliefs a tough needle to thread without getting banned.
its also harder and harder to find a moderate republican that is under the age of 50.
Eh, that group has long been gone - I think at this point it's primarily the dogpiling and accusations of being inherently sexist or racist from the get-go.
As a long time lurker but a new poster I'd say that the biggest issue is just the usual internet thing of "anyone even slightly to the right of me must be a right wing bigot". In reality people (especially the ones who even care enough to take part in discussions about politics) have nuanced views and priorities. Very few moderates hold all the stereotypical views of the american right.
I'm not american but I'd probably have a very tough time fitting into either party over there. I did do the isidewith.com test a while back as thoroughly as possible (all extra questions, question priorities etc.) and I ended up with sanders in the lead, followed by trump, paul and clinton. Each at around 75-65%. And at home I usually vote right but still support universal healthcare, free education, gay marriage etc.
If I was voting in the states I'd be pretty pissed with the Dems' positions on immigration, affarmative action etc. and frankly scared by the younger generation of Dems' support of things like completely banning guns, hate speech laws and so on.
But on the other hand maybe even more pissed at the GOP's utterly stupid stances on abortion, deregulation etc.
Depending on the company I could be called right or left. If I started posting in GAF threads about social issues I'd probably get called right since I find the collectivism and focus on race / gender over income / class in the current wave of young progressives slightly troubling (and quite frankly illiberal as a lot of these talking points abuse personal liberties in favor of making demographic X look better on a spreadsheet) and were I in the states I'd be terrified that those same ideas could move from the young to the actual politicians.
And unless my hunch is completely wrong I'd be pretty comfortable with guessing that a lot of the younger conservatives who actually do think beyond "TRUMP STRONK" and are somewhat moderate might be quite close to me politically. And it's exactly those black and white "you're a hypocrite" "no you're a racist" discussions where people like me begin to tune out.