Actual revenue per user for Facebook in the US and Canada is $26+ / quarter or over $100/year... That is on the order of $10/month [1]. So if a company wanted to be as profitable as Facebook, and not make money from advertising, they would have to charge $10/mo. That is more than I am willing to pay for Facebook -- my friends have my phone number.
If you think profit of providers like Facebook should be limited then that's a regulation issue. Personally I don't think that should be the case.
It is possible to provide the service Facebook provides in a fully encrypted manner. Individual companies would require subsidies and audits to ensure encryption. Essentially regulation.
Another alternative is fully encrypted, distributed services where personal CPU and storage are used to support the service. This is possible through systems like Diaspora or Mastadon, but there is an ease of use / network effect issue there.
I just don't think it is as simple or inexpensive as pennies a day. Or to push a company to charge that little would require regulation.
[1] https://www.google.com/amp/s/www.cnbc.com/amp/2018/01/31/fac...
Would I be willing to pay 10x-1000x times that for a half dozen $10/mo subscription? No.
The problem is is that (lack of) apathy is a strong signal, ripe for price-grading, and boy do they price grade!