I think the main reason is that very few people are actually interested in hearing views that seem to challenge their preconceived notions - even if what’s being said doesn’t actually contradict them. People are constantly on the hunt for “the other,” and the bar for labeling someone as the enemy based on a few wrong-sounding noises is extremely low here. The capacity to give anyone the benefit of the doubt is almost nonexistent.

It’s a team sport, and when they suspect someone’s not on their team, the instinct is to tear them apart. Most people aren’t interested in changing minds - let alone being open to having their own mind changed. They just want to sling dirt and rack up upvotes from the audience.