This article does not support its clickbait headline with much in the way of facts. "Analysts estimate" that Apple's ad revenue could drastically increase. Insiders talk of a reorganization. There might be ads included in more apps. The headline makes a major assertion the body does not support.
Moreover, the chart of 2021 ad revenue shows Facebook at $114B, Apple at $4B. The article text says Facebook worries Apple’s changes could cost them $10B, less than 10% of their 2021 ad revenue and more than double Apple’s total . The narrative doesn’t match the numbers.
Yet, just look at Amazon's if you want to see how fast it can grow. Or how the app tracking prompt popup compares for their own (pretty CTA for "Yes personalized ads please!") vs third parties ("Oh no I don't want spyware!").