.... In this particular case, Twitter probably has made a lot more profits than the penalty amount ($150m) by selling their user data. So they can get away with it even after paying the fine and I am pretty sure they will come up with a creative way to avoid this penalty anyway.
It's what I was thinking too. This amount is just a slap in the wrist for these big platforms.
Where do these fines go by the way?
The companies they sold user data to should be fined as well. This will discourage others from the act but I'm afraid it has become a tool that's become necessary in today's market. Private companies pay good money for user data, it helps them know what to sell you and how to sell you. It's all geared towards advertising and selling their products. Google is the biggest offender of this crime, they spy on their users all the time.
First thing you have to look at is that are they prohibited from getting these kinds of information? Are they also prohibited from using it and selling their prpducts? Personal information are protected but I don't think it's treated the same way as buying illegal drugs.