The universal problem is that there’s no shared definition of what a downvote represents. Is it “this is spam and should be removed”? “I don’t like this”? “This doesn’t belong here”? “I want to see less of this”? “I disagree”?
That’s not even a Reddit problem - it’s innate to any social media voting apparatus. Extend it to Facebook, even. Does the laugh reaction mean I’m laughing with you or at you?
Most comments and posts I’ve downvoted have been because I accidentally swiped too far right and my upvote changed to the downvote action and I didn’t even notice. So those downvotes don’t even mean anything!
I think the right answer is to stop worrying about votes. Even if they all mean the same thing they’re still meaningless. It’s better to change your post and comment sorting setting than to try to social engineer a way out of it.
Not exactly what you’re asking, but it’s also worth checking your local library. Some of them grant their cardholders access to external sources that might overlap with what you’re after.