One of the problems with walled gardens is you rely on the groundskeeper to keep it maintained. And if they're incompetent or absent, you're just screwed. There's no way to manage any aspect of most of the iOS photos metadata, like people. There's no interface. It's been years.

If you want to reset the People database in iOS, you have to let it scan all your pics, go into the list, then drag-select every face.
Then it will ask you to reset it.
There is no option for this. Because it's too much work. So it's behind a stupid undiscoverable quirky hack.

By not providing a way to manage any aspect of the low-level state of a system, you make it increasingly inscrutable and subject to tacked-on bloat with no user recourse.

State inconsistency is the root issue in many problem scenarios.
You fix this by resetting the state.
But if you cannot access nor interact with the state, you've created fragility.

This is what Microsoft did with the Win10 Start Menu and customers have paid the price for years.

At one point, the solution to fixing the Windows 10 start menu was literally by deleting your entire user profile.

This is not the right way to reset state.

Resetting state is a reliable way of correcting many, even the majority of, electronic systems problems. They get into unanticipated states by their unobservable nature.

If you understand how application developers store and reference state, you can fix basically anything.

One of the things Apple did absolutely correctly in iOS is tying the application installation and application state. If you remove an app, its state gets removed.

This is not the case in general-purpose PCs like Windows for most operations. The state is unaffected by uninstall.

Reinstalling applications to fix them is generally a worthless operation that worked because of architectural issues in Windows 9x. Files don't spontaneously get corrupted, disks are extremely reliable.

But, sometimes the uninstall operation resets state, which actually fixes it

In principle, an application developer can store state anywhere and by any method they want in a general-purpose PC. But often there's only a few things they do:

-AppData\\Local
-AppData\\Roaming
-ProgramData
-HKCU\\Software
-HKLM\\Software
-Temp
-System Temp
-HKLM Service Parameter

In this context, "state" is the configuration settings and data of an application that's preserved between launches.
There's also memory state, which can be cleared by just restarting the app. But everyone understands that. Durable state is much, much less understood.

All programmers should make it trivial to reset the state of their application. This would fix a lot of their support issues.

Look, I've been doing this a long time. My responsibility was, "any problem with the PC even if they pirated the software."

You just reset the state.