The reason other sm platforms don't pay people to vote is because they prefer to use an algorithm to do their curating for them. Our likes and shares are only a small part of their algorithm. They don't care what we like or want to see. They care about what their stake holders want us to see.
An algorithm is cost effective but it's centralised and censored so we don't even always know what an algorithm is propagating or censoring.
Auto voting isn't always bad. A curator can decide this author should always get my vote without me always reading. But a responsible curator would regularly check and update their auto vote list, and be available to remove their vote on call in important circumstances.
Those with the most stake need to be the most responsible and careful.