Epic Games (Fortnite Developer) is suing Apple for removing Fortnite from the app store. Apple/Google takes 30% of all the money that comes from the app through the App store/Play Store, Epic Games implemented a new way of by passing that 30% charge to Apple and Google, so both company removed the games because it doesn’t comply with their TOS. I haven't seen any news about Epic Games suing Google, which is weird.

Source: https://www.cnn.com/2020/08/13/tech/fortnite-apple-store-removed/index.html