Internet point giving is pretty recent phenomenon (as is all of social media). I think there are important social differences to approving in person and giving internet upvotes. You are way more connected see the effects of your approving and can conveoy more subtle messages in the same go.
Giving voting too central a role in our websites might be analgous to having implemented a reinforcement AI as president/world leader without solving alignment. Voting might be institutionalized demagoguery that we are unlikely to catch in critiques.
Having a bad utlity function gets critiqued quite closely. Having a vote button with no guides how it could/should be used blackboxes the method actually used. There can be an issue where irresponcible voting is having adverse effects. It's like not locking your door to avoid getting a burglary, you can't break and enter if there is nothing to break.
One of the issues is that you will struggle to be meaningful if more attractive webpages manage to be attractive because they allow for self-expression or because so many other users are using or viewing them. Part of tyhe problem can be that if you read a news paper you get nicely editorialised content but if you get your news on reddit you can have fun fights in the comments so people will pass on "boring" newspaper because they can't fullfill their expectation of engagement.