Well sure.... The Republican isn't the one with disparaging comments being directed at them and their associates. They could be called a Nazi, but if that isn't true, then it should effect them.
Meanwhile, nigger, fag and mudslime gets thrown around and it's expected to have the same sort of nonchalant meaning, with much worse connantations.
Don't forget racist, misogynist, islamophobic, xenophobic, homophobic, transphobic, classist, ableist, authoritarian.... That's the list from the video itself and there are lot more disparaging things the left likes to say.
And the comment this guy showed himself deleting contained no insults or slurs, so their desire to not be confronted with different political beliefs goes likely beyond slurs.
and it's expected to have the same sort of nonchalant meaning, with much worse connantations.
While the mainstream and especially the mainstream left has absolutely no problem with nonchalantly saying things about whites or males that they would NEVER find even remotely acceptable to say about any other group.
Because either they redefined sexism and racism such that they themselves are exempt from it or they painted the other side as such evil monsters that everything is acceptable.
This becomes entirely obvious when you replace "men" or "whites" with "blacks", "jews" or "women", like this quick example: https://i.imgur.com/4klIkY7.png?1
"Never be too proud to delete a comment" https://youtu.be/wmVkJvieaOA?t=693 From a video later into the series where he shows deleting a comment that's harmless.
Both the left and the right make use of bad rhetoric and uninformed arguments but that's the big difference between them, most popular youtubers on the right would not delete a equivalent comment. And republicans are by fare more willing to tolerate opposing viewpoints compared to democrats, here's a survey that demonstrates this.