Internet's most magical product, devil's favorite sin - Vanity.
People who aren't heard anywhere, even their siblings/spouses/kids/friends don't give a hoot to what they're saying, they google stuff and post online and in return get 'likes'. It boosts their ego, they become superhuman in their own capacity. Their chests broaden and they get the long lost sleep at night. Even funnier is the batch on FB who post Faraz's poetry, receive likes and then in comment section post 'thanks' - bhaiyya apka input kya tha faraz bhai kay iss shair mai?
Now not everyone with s-loads of likes is necessarily suffering from ADHD, some are legitimately knowledgeable here. They don't give a rat's behind about likes and dislikes. They are less, but they are there.