I'm more talking about the greater relationship between the right and left, where the right takes itself as entitled to being "genuine" convictions while the left is just like, a disease or something. Abortion and the religious right just happen to be the place where I've seen myopia most often.
Not that I disagree with you, but, Conservatives see the same behavior on the Liberal side. Liberals are very self-assured of their "right way of thinking" on issues like gender equality, gender identity, the environment, race, tax rates, public vs. private education, so on and so forth. I listened to one conservative commentator not too long ago basically level your quote at liberal democrats verbatim.
To Conservative Republicans, Liberal Democrats are smug know it alls who are arrogantly assured that they're on the correct side of a belief or value. Clinton just further reinforced this perception with the deplorables thing. A lot of Conservative Republicans I work with or around took that very personally, it's exactly the kind of thing they've always believed LDs felt and Clinton simply validated their world view that half of America thinks they're cretins, so, fuck half of America. And even after they've retreated from supporting Trump somewhat, that shit still lingers in their minds.
But the TLDR is, every side has its convictions. Both the Left and the Right's stem from a general belief they know right from wrong. The Left may source their beliefs from rationality or equality, and the right may source it from tradition and religion, but to me it boils down to the same thing at the end of the day: both sides are intractable because compromise of any kind feels like a violation of their beliefs. And in many cases, it is! You can't convince a LD to vote for a Trump policy they hate simply in the name of getting along. And CR demonstrated with Obama the same thing is true.
I'd say we need a centrist to mediate between the parties but all that would happen is they would fail one or another purity test either party holds, get cooperation out of no one, and have their nuts or ovaries neatly divided between the parties. Although, and this is my bias showing, CRs are way less willing to compromise than LDs IMO. They've been in all or nothing mode since Obama's 1st term. If you can't get exactly what you want, just start saying X politician is destroying America loudly and long enough until people start believing you. It's a win-win as long as you don't have any self-respect.