You mean “There is lots of reasons why this would be interesting to game developers”, goes on not mentioning a single one ?

Why do I even bother to reiterate the rest of the paragraph that you did not quote? Game developers and their users are regularly exploited by App Store and payment processor fees. Transfers of ERC721 and ERC20 on an L2 is negligible by comparison:

https://l2fees.info/

Apple, Google etc aren't going to allow you to bypass their in-app purchasing system.

Has been tried many times before and just results in your app being banned.

Google recently changed tack on NFTs, allowing them in the Google Play stores, which means it is now allowed by their policy to circumvent the store fees for this use case.

But the more obvious solution here is to not use the walled garden app stores at all, if you plan to monetize and distribute assets via crypto. Thankfully we do have the web and PWAs.