As this article shows, Apple is slowly moving in that direction for their PCs. They aren't going to be satisfied with locking down their phones only.
An App Store from which you can download software with confidence is a pretty sensible first step for most users.
Complementing that with a Notarization service for apps that can't live in the App Store, while still giving both users and developers confidence that the user is installing the "real" app, and not something malicious, seems like a pretty sensible way to protect most users outside the App Store.
And if all else fails, there are ways to allow running that un-Notarized, non-App Store app that you're sure you trust.
None of that seems like something that inherently means to take away your ability to run what you want on your PC, it just sounds like a common sense approach to giving your users confidence in what they run, and guiding them to do so safely by default, while allowing overrides as needed.
Are these ALSO things that Apple could use to lock down your PC completely?
Sure... but then, why bother with any of it if that was the intent?
They already have Mac App Store, and they already have the infrastructure to deal with a "whitelist only" approach, so why bother with this Notarization and Gatekeeper stuff at all?
Don't get me wrong, there's plenty of room to criticize Apple for their implementation. They are clearly figuring out some of this as they go, and trying to find a proper balance. That isn't easy, despite how many people make it out like it is.
Give the average user too many prompts or chances to override security, and they will do that, every time, without thinking it through.
On the other hand, bury the overrides too deeply, and risk making things miserable for the developers and power users who need to use your platform freely.
So far, I see only evidence that Apple is trying to find that balance, but no evidence that they intend to lock the entire platform down entirely.
Are they doing it perfectly? Clearly not. But I think if we're being honest, no other platform has either. I appreciate Apple's approach the most so far, but time will tell if they are able to figure this balance out or if another platform will at some point.
Change management. For the same reason why Ebay had to backtrack changing their background color and do it again, slowly.
But as someone who has been using Macs on and off for about 10 years now, I've heard people shout that Apple was locking down Macs from the moment the App Store was created on iOS (and long before it came to MacOS). So far, that hasn't happened.
Is it possible this is the next step in a 10+ years plan to "boil the frog slowly"? Of course! Not sure how they would accomplish this without also losing the developers they need to continue making both MacOS and iOS viable platforms for users, but I guess if they just don't care and want to lock everything down, this could certainly be one more step towards their long term nefarious goal.
But it also still seems like a reasonable step towards making their platform more trusted and secure for the average user while continuing to give devs and power users control.
So far, I see no evidence for the former, and enough evidence for the later, that I'm not too worried.