You are overthinking it. A lot of software just doesn't need elaborate updates.
For one utility app that I sell, I just build a new version every couple of years when it's no longer compatible with the latest OS, and people still buy it. There really is no need for updates for some apps.
If there is demand for updates (eg. because customers want new features), then you can just sell it as a new app. People who want to upgrade can get the new version. And people who are happy with the old version can just continue using that.
The folks who complain that they can't sell yearly updates on the app store are basically just trying to sell subscriptions without calling them subscriptions. They should just sell their apps as a subscription instead. It's not really pay-once if users have to buy an upgrade every year.
I don't think that's really the same concept, though.
Yes, a utility app might be "done" at some point and only need updates when the App Store requires you to build against a newer iOS SDK. Fine. But many apps go through large changes over time and accumulate large improvements that might be worth paying more for.
Selling a new major version as a new app is a clumsy experience for users. They need to find the new app, install it, somehow transfer all the data and settings from the old app to the new, and then delete the old app. Most of that isn't something the app author can automate or do for the user.
I agree that some people might "abuse" this sort of functionality to sell subscriptions without selling subscriptions. But so what? Under this imaginary App Store upgrade flow, the user could also choose to keep using the old version and not upgrade. That gives the user more choices, not less.
For one utility app that I sell, I just build a new version every couple of years when it's no longer compatible with the latest OS, and people still buy it. There really is no need for updates for some apps.
If there is demand for updates (eg. because customers want new features), then you can just sell it as a new app. People who want to upgrade can get the new version. And people who are happy with the old version can just continue using that.
The folks who complain that they can't sell yearly updates on the app store are basically just trying to sell subscriptions without calling them subscriptions. They should just sell their apps as a subscription instead. It's not really pay-once if users have to buy an upgrade every year.