Just because you're paying $10 a month does not mean that Meta will stop farming your data. Sure, they won't shove you any ads, but they will stockpile data for the day you decide that $10 (it's not really $10.. they will increase this price 2-3 years down the line once they feel they had gathered enough users, the Silicon Valley way) and then pump you with ads that cater you.
They don't directly sell data, nor does Google. They analyze and use that data to sell targeted ad space.
There are data brokers that gather a ton of data and openly sell it, but Facebook isn't one of them. Their customer data and the resulting ability to sell extremely specific ad space is probably their single most valuable; why would the sell it itself when they can sell the access it grants instead?
They sell access to data (i.e., ads) - that is far more lucrative than selling the data itself. Only companies that are bad at tech just sell the data (credit card companies, retail, etc)
Cambridge Analytica was far more stupid - that was them just giving away data for free. Their old Facebook Apps APIs were wide open to collect whatever for free for anyone who would use your app (CA made those "do this fun quiz and invite your friends!" kind of FB games) and the APIs just said "we require you to delete this data when the user is done with the app" with no way to enforce it