Then focus on the people that do want it - which by the count of the number of people who say no to Facebook tracking on iOS, is a very high number. Enough to be of material impact to Facebook's bottom line.
The law does not allow Facebook to refuse service to those saying no to tracking. If they were faced with that choice, I am sure most users would've made a very different selection.
And the current privacy laws in EU make the free services illegal. How is that any better than the scenario where paid services did not exist?