Both sides do it when you're in an echo chamber.
I'm left of center and typically vote Democrat, but I'm not insane liberal like a lot f the folks that live around me. I keep my mouth shut about my beliefs because people that are really partisan will see you as "one of them" is you're not as hard core liberal or conservative as they are. My GF has very similar views to myself. She leans left and typically votes Democrat. She doesn't talk politics at all when at work because she works in environmental science for the state and is surrounded by activists and frothing at the mouth Pacific North West liberals. She's originally from North Carolina and thinks these people are fucking crazy.
I've experienced the same shit from the hard right while hanging out with small town guys that I grew up with when I go home for the holidays, to watch the superbowl, fights etc. I try not to get into conversations with them, but after a few beers, I'll make the mistake of expressing one of my views like not being a fan of open carry or thinking a border wall is silly only to get called a libtard and have it explained to me that I've been indoctrinated by going to college and living in a city. You can't argue with them because they're so sure they're right and you're a fool that you can't really even have a conversation with them.
The big difference I've noticed between hard core folks on the right vs the left is that the ones on the right will still befriend and associate with someone that they disagree with on politics. I can still BBQ it up and hang out with guys that are straight up Ned Flanders type Christian Conservatives. The hard core lefties I live and work with usually will circle you out unless your politics are pretty on par with their own. There's just a much more prominent sense of righteousness with hard core lefties that makes them a bit more unfriendly and unwelcoming. The folks on the far right want you to be like them as apposed to the folks on the far left hating you if you're not like them. Obviously these are generalization, but this has been my personal experience.