So users can profit from their content? They won't profit from their content, it's nearly worthless per unit. It's only in the vast total sum that there is any value, and only because it's held by one entity. If you distribute it per post or per person, it's very close to meaningless. $20 billion is a lot per year to one entity; $20 billion per year to two billion people, is not.
If you were generous with Twitter and assumed they can generate $400m per year in profit and then chose to distribute that to the userbase, you're talking about ~$1.30 per active user per year. If you tilt the value distribution toward the most active, famous users (whose tweets are far more valuable in regards to monetization), then you're just destroying the distribution premise to begin with by concentrating the wealth in a slightly different manner: Taylor Swift doesn't need to worry about earning $35,000 per year from her tweets, and Joe Smith getting $7 from Twitter for their 1,278 economically worthless posts also does not matter.
Ultimately you just end up with a YouTube outcome if you value tilt. A small group of rich users earning millions of dollars on FB or Twitter, and everybody else entirely failing to earn even minimum wage for the time put into their economically low value posts. How does that really change the equation vs the people that are capturing most of the value today? Taylor Swift can already capture the value generated by Twitter and Facebook, she can buy the stock.