The upvote system is way too rudimentary to work efficiently. The upvote incite people to post to become more popular, not to post more interesting content.
One metric is not enough, the upvote system combines both "funny" and "interesting" in the same metric. Soon it's the funny content that is pushed to the top, because it's a more common characteristic. But this is how you get memes, emotional and basic screenshot of tweets to the top of the frontpage. And this is probably what you don't want.
So either we add more type of votes,for example two arrows, like an arrow "interesting" and another arrow "funny" or we get rid of them, leaving only the "report" button.
Get rid of reputation too. Some people are already chain downvoting in rage. What good do you think will happen out of a reputation score? People will just spit on you. People are emotional, don't put a gun in their hands.
"The downvote is useful to get rid of antivaxx"? You have a report button for that. And while the downvote button gets rid of antivaxx, it pushes memes to the top, destroying the platform itself. The benefit of the downvote button doesn't compensate for the flaws of the voting system.
The best way for an antivaxx to get his content visible? It is to get blocked! If he is blocked he cannot be downvoted anymore afaik. So it's all good for him. Even the block system doesn't really work as intended and has nasty side effects. Because yes, you won't see it, but other will, and they will adhere, and they will upvote and post more antivaxx stuff, and inspire more antivaxx people.
And I'm not even starting with the bots and scripting systems, which will detect who downvoted you and will "revenge downvote" for you. Do you want all your post to appear with a starting minus 5 attached to it because you posted about veganism 3 months ago? That's what you will get. All it takes is 5 people who don't like the way you talk, and a script. And all your posts will go down the drain as soon as you post them.
--> The system need either higher granularity or we need to get rid of the voting system, and keep only one button: "report", with a mandatory 60 characters comment with it. <--
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