I think the gastropod is basically on point. The democrats aren't beacons of virtue or rationality by any stretch of the imagination, but its a strange kind of self-imposed blindness to pretend the two political parties are playing the same game here.
We can simultaneously see that partisan politics isn't completely rational and also observe that one side, for various reasons, is working that irrationality harder than the other.
The question isn't whether they're playing the same game. Indeed, it'd be surprising if they were, since the goals and principles of the two parties are often quite different. The question is whether "aha, that other party has decided to do the wrong thing rather than the right thing" is a helpful way to conceptualize the difference.
As another reply to you has shown, it's very easy to find specific differences and elevate them to an all-encompassing explanation, if that's how you decide you want to look at things.
A study at Dartmouth found that 45 percent of Democrats say they would be uncomfortable rooming with a Republican. Comparatively, only 12 percent of Republicans said rooming with a Democrat would make them uncomfortable.
My anecdotal evidence bears this out. Progressives tend to be far more intolerant of opposing viewpoints than conservatives.
I would find it uncomfortable being a roomate with an outspoken holocaust denier. A holocaust denier probably wouldn't find it uncomfortable being my roommate. I would wager this generalizes pretty well to holocaust accepters and deniers as a whole.
Is the takeaway from this that holocaust deniers are more accepting people?
We can simultaneously see that partisan politics isn't completely rational and also observe that one side, for various reasons, is working that irrationality harder than the other.