I have done a good research on decentralized social platforms and social media platforms that rewards its users and i found a number of them such as,sola,yours.org,wildspark,selflerry, lit just to name a few but steemit still tops the list.
Its way easier to get rewards on steemit than any other decentralized social platforms. As much as people criticize the rewarding system on steemit, its actually way better than rewarding systems on other decentralized platforms and actually works. The rewards on these other socialplatforms is in pennies and takes a significant amount of time to accumulate to a reasonable amount that can be transferred. As much as social giants like facebook might develop their own coin, i highly doubt they will use this coin to reward their users. Their main intention is to keep up with the current technology which is basically blockchain technology. I think if the social giants develop their own coin,these coins will mainly be used to transact businesses and pay for services such as adverts on such giant platforms . The most probable thing they will do to ensures users benefit is by probably introducing a tip button where a user can tip another user.
I highly doubt it will be possible to mine coins on a platform like facebook,instagram or twitter through likes if at all they come up with their own coin or token.
Yes the rewarding system on Steem may not be fair but its actually unique and seems to work compared to other platforms. I would give it a 7 out of 10.