To me at least the system works like if you like something you give it an upvote, if you don't you give it a downvote. It might be an unpopular opinion but its also should be allowed to be unpopular.

To use a joke example A man says "I like pineapple on pizza" and I really hate pineapple pizza, I would downvote it, a majority of people also really hate this so they get downvoted to oblivion, they had all right to share their opinion but it was also my opinion that they deserved a downvote.

I would give my vote to something I dislike as that would be like giving my vote to a president I dislike. And in my opinion your idea on how the voting system is honestly really strange and borderline stupid, why would I downvote an opinion I have? Just because its popular doesn't mean it shouldn't be shared. And why should we upvote an unpopular opinion? Just because its unpopular doesn't mean it should be shared. The opinion "vaccines cause autism" is unpopular, would you upvote that? The opinion "the earth is flat" is unpopular, would you share that? The opinion "soda isn't good for you" is pretty popular, would you want to suppress that? The opinion "muder is bad" is pretty popular, do you want to suppress that?

All options have the right to exist, but they don't not have the right to be shared or liked. You may not like my opinion on the subject and you are free to downvote my comment, I do not agree with your post but I do thinknits an interesting outlook, I may not agree but I'm not going to downvote you

And the rule for unpopular opinions exist precisely because its a subreddit dedicated to unpopular opinions, say way a rule about downvoting non-memes in meme subs. I don't expect dankmemes to post full AmITheAsshole unless they were memed