Read my post again, no they don't; the version of the app in the store is one version and it's compatible with your device or it isn't, this is how apps are deployed and is the reason why they often break compatibilty with a major update to the operating system.
Console games require different SDKs for deploying the game, so the marketplace will simply segregate content based on the hardware.
Smart delivery makes this a behind the scenes operation so you can never have the wrong version, this is completely incomparable to smartphone appstores, there's only every one version there.
In other words, it's impossible for them to have similar processes, because they literally aren't doing the same thing, because even if your phone is "underpowered", all the store does is check if you have the right OS and region, you'd still be able to run a game on a low end phone, even if it will run like shit at ~10fps; because there isn't a version made specifically for other specs, the app is either "compatible" or it isn't, because there's always only one global version of it deployed.
Smart delivery will then overwrite files where needed, like the update for avengers was 106.9gb, but it didn't require that. It only required 40gb since the rest of the files were overwritten, this is a pretty big deal when dealing with several different SDKs; normally you'd have to manually download the other version.
No, it isn't, that's just the "record" of what you own/have access to. This "record" also exists on xbox and is how you transfer from an xb1 to a series x|s, and yes that's similar to smartphones, but it has nothing to do with smart delivery; smart delivery only ensures you have the right version of what's in your "record", and this is important because of the SDK differences, the versions are made with different specs in mind.