https://wccftech.com/apple-will-let-certain-apps-have-an-in-app-link-to-external-website-for-account-management/

Currently, the Apple App Store guidelines require all the developers to sell digital services and subscriptions using the company's in-app payment system. This means that the developers cannot redirect the users to an external website to make a purchase or manage their accounts. However, this is about to change. To close an investigation by the Japan Fair Trade Commission (JFTC), Apple has agreed to allow the developers of "reader" apps to include an in-app link to an external website so users can make the payments or manage their accounts from there.

For those wondering, reader apps are the ones that offer previously purchased content or content subscription for digital magazines, newspapers, books, audio, music, and video. Some of the examples of reader apps include Netflix, Amazon Prime Video, and Kindle.