Upvotes/downvotes are unfortunately a fundamentally flawed concept. They originally served as an superior alternative to forums' previous sorting method of most-recently commented, but they are far from flawless themselves.

My ideal alternative would be some kind of customisable sort order chosen by the user that uses some kind of sentiment analysis of the text to find the kind of posts the user is interested in. For example, you could sort by whether post look serious or joking, how long they are, ratio of words to hyperlinks, etc. Could also filter out ragebait and similar rubbish.

Of course I can see downsides - performance considerations, and it would only work for text posts and comments, but it's just an idea off the top of my head.