Facebook's ad revenue for 2018 was $55.8 billion from 2.7 billion MAU. That means each user is worth $20.67 per year. In reality, not all users are worth the same, and as an English speaker, you're probably worth at least double the average. So, figure $40 a year to remove ads from Facebook, not single digits. Now what about the other 10,000 websites you touch each month?
About $50/month for a family plan should be fine for a completely add free internet. How that fee is distributed across the different sites I visit is an administrative issue.
