As Zeke Miller finds in ORI's presentation, "liberals were significantly more likely to have blocked someone than conservatives," and specifically, they block people "because of their political views."
An old adage is that while conservatives think liberals are wrong, liberals think conservatives are evil. This has been proven true time and time again - liberals prefer to pretend like there's some inherent defect in conservatives rather than acknowledge that there's such a thing as reasonable, honest disagreement.
This brings to mind Jonathan Haidt's research that conservatives understand liberals a lot better than vice versa. In personality tests, conservatives are able to "fake" being a liberal, while liberals are just confounded as to what conservatives think and believe:
hat Haidt found is that conservatives understand liberals’ moral values better than liberals understand where conservatives are coming from. Worse yet, liberals don’t know what they don’t know; they don’t understand how limited their knowledge of conservative values is. If anyone is close-minded here it’s not conservatives.
Here's Haidt discussing the findings of his research with The Economist.