I'm pretty sure you're wrong. Looking over the part where you imply that the MacOS App Store is the standard way to install Applications on MacOS (opposed to dragging the application to the Applications folder), let's look at what the system you're referring to actually does:

https://developer.apple.com/documentation/xcode/configuring-...

Show me where it says a program installed from the MacOS appstore will be unable to read the user's files unless the user explicitly authorizes it. Here's how it actually works as far as I can determine: The application developer grants their app the entitlements to read user files. The user may see that entitlement before installing the application, but thinks nothing of it because of course the program operates on their files. This does not protect the user against a malicious program being shipped with those entitlements and a plausible pretext to justify it. Example: The user downloads a program to read some kind of unusual file for work, the program grants itself access to ~/Downloads because of course it needs that, then the program instead reads ~/Downloads/your-tax-documents

This system only protects the user if the application was legitimate, refrained from granting itself the relevant entitlements, then got compromised by an attacker.

>Looking over the part where you imply that the MacOS App Store is the standard way to install Applications on MacOS

That is the standard way. An app that has its own custom installer or patcher/updater is by definition, using a non-standard install procedure.

But even if it wasn't, it definitely is the standard on Linux, where package managers are the norm.

>The application developer grants their app the entitlements to read user files.

Flatpak works in exactly the same way.