That’s correct, Apple said apps are not allowed to limit functionality based on whether users allow them to track or not. I’m guessing what will probably happen is they’ll have to include a message to the user saying that tracking keeps the app free to use, and that if too many users forbid tracking, they’ll have make the app paid. Not sure how effective that will be. Apps will probably start getting much more expensive, or I should say they will start costing their true cost.
I do think there should be a way for developers to offer two versions of their app, a paid/non-tracking version and a free/tracking-required version, so that customers have the option. As of the new rules, it seems like the tracking-required version won’t be possible.