Not just republicans / politically right-wing oriented folks. From my experience you encounter this everywhere where people haven’t learnt how to have a civilised discussion. An important part of this is the ability to self-reflect and distinguish emotions from opinions from facts. Humans are emotional beings in their core and therefore the most are fallible. It’s only natural to resort to an emotionally driven and often stubborn defence mode if one encounters a contrary opinion. Even more so if that opinion is expressed in an emotionally loaded manner. It’s unfortunately a very counter-productive human behaviour.

And we have that a lot on the internet. Sadly.