People want their biases validated and they don't want to be the contrarian, even if it means being wrong. I think it's the same reason the same questions and answers appear on askreddit all the time. People get to upvote things the they agree with easily and don't have to work hard to figure out what the right answer is. So now when the post is fact based instead of opinion, but they already have a pre-formed bias, they still upvote for the 'popular' answer instead of the right one.

For example, many times things get downvoted purely because Trump is mentioned, even if the statement only contains facts. Now there may be comments deserve downvotes, but downvoting purely because it mentions Trump is validating the bias that Trump is bad. You could do the same but opposite with Elon Musk, because he has a positive bias to most redditors.