Actually sounds spot-on with regards to the parent comment: by his/her logic one way to deal with social media is to make sure you see everything, else you might miss something relevant. Nerve-wrecking if you'd ask me.
On the other hand, some learning algorithm which figures out what is relevant to you sounds interesting at first but could, in my opninion, quickly lead to creating a bubble in which you only see what some algorithm considers relevant and nothing else. Now I get that some people like it that way, and in the end we all live in some kind of bubble, but still, I'd rather keep options open and actively look for new things I know nothing about.
Not sure if you're being sarcastic, but ... Facebook seem to classify posts as important if they get more than the usual number of peers attention, so you get major life changing announcements (births, deaths, marriages). I don't know if they solely use votes, or if they weight that with word analysis, or do something clever like matching you with other friends who upvote similar things and so boosting the chance you see posts if they upvote them (I imagine they do but perhaps use simple metrics for 'life event' indications).