That might be the average price Economist readers would pay. I suspect it would be a lot lower for most users.
That aside - FB never gave users that choice. Where many media services - including AOL, streaming media companies, and newspapers (and the Economist) survive by charging a subscription, FB has never attempted to use that business model.
Why? Because FB has always been a data harvesting and user monitoring/profiling operation that happens to operate a social media front, rather than vice versa.
Ditto Google for search.
And "telling users about it in some capacity" is very different to giving users a list of buyers and full details describing what their personal data was used for.
Realistically, no one outside the industry - and not that many people in the industry - understand where this data ends up and what it's used for.
Pretending otherwise is casuistry and special pleading. There is no way users can estimate the true value of their data, either individually or in aggregate - because the value is determined by buyers who remain hidden and unnamed, and neither FB nor the buyers are obliged to explain any part of the process.
There is no informed consent here. It's a perfect corporate asymmetry, and very much designed that way.