TL;DR: Quest 2 owners will experience larger file sizes due to Quest 3 game upgrades, as developers currently lack a convenient method to offer separate builds for the two headsets. This situation may change in the future with Meta’s plans to extend support for separate APKs. (via ChatGPT)
Not sure how comparable this is here, but on iOS some time ago Apple made it so that the apps you download only include the relevant stuff for your device, which made them a lot smaller.
Yes, APK can do this also. But before downloading the application, your device tells the server, which type of device it is so the server can tell what APK should it give. But Meta owns the store, so the device not only should support different “user agents”, but the server should also implement the API for the developers to differ their builds accordingly. Meta can decide not to do this to force older models (and with lower storage) to move on to more costly devices. This is toxic business behavior, but it’s their business and their choice to make. We can only ask and hope.