Your comments here reveal two big fears for each major release of macOS: that it’s somehow becoming more locked down and slowly merging with iOS, and more specifically that Apple is going to block apps and command tools that aren’t notarized. In both cases, I think they’re the natural result of unfounded rumour and a misreading of what’s actually happening within macOS.

Back in 2014, Apple had two operating systems, OS X and iOS. By the end of the following year, it had doubled that number with the addition of watchOS and tvOS, then belatedly added iPadOS in 2019. This year it has added another, visionOS, bringing the total to six. Rather than sprawling over multiple devices as they were when iPads were first launched, these are diverging to cater more specifically for the features and capabilities of Apple’s main product lines.

There’s an even clearer picture if you look into the heart of those operating systems. Although there’s a lot in common between their kernels as they’re each based on XNU, there’s also a great deal that remains distinct. macOS has long benefited from swap space, but while iOS also has virtual memory, it doesn’t use swap storage. One of the improvements made to iPadOS 16 last year was the introduction of swap storage, just one example of how it’s diverging from iOS.

Much of the power within macOS comes from its kernel extensions. Of the nearly 600 that ship in Ventura, the great majority are unique to the Mac. For third-party developers, modern replacements for kernel extensions are system extensions and their kindred, which only exist in macOS. For all the compromises that might have been made in APFS, it too has plenty of features like snapshots and clone files that only come into their own in macOS, where they’re essential to Time Machine, another major feature that’s confined to macOS. Then there’s lightweight virtualisation, the Finder, Stage Manager, multiple user accounts, background items, Mission Control, external storage, and so many other distinctive features of macOS.

Pessimists convinced that Apple’s six operating systems are going to merge into one, point to outward signs such as System Settings, which is supposedly more like Settings in iOS. While changes in Ventura have taken some getting used to, when I do have to return to System Preferences with its ridiculously small fixed-size window, I for one am only too happy to move on with Ventura. Apple should have brought that change even sooner, as it makes long lists of privacy settings in Privacy & Security far more manageable, a problem also confined to macOS. But it really does have nothing whatsoever to do with Settings in iOS.

Many of Apple’s more than 10,000 engineering teams work across platforms, and so they should. We all expect a consistent and integrated experience across our Macs and devices, and there’s no better way to achieve that. Improved integration of tools like SwiftUI also benefits all, and rumours that Apple is abandoning its single-platform interface libraries AppKit (macOS), with its origins in NeXTSTEP, and UIKit (iOS, iPadOS and tvOS) are palpably false. A glance at the AppKit release notes for Sonoma confirms that. Unlike some operating systems, Apple’s maintain clear separation between computers controlled using mice/trackpads and keyboards, and devices driven by touchscreens, and separate human interface guidelines are provided.

Apple has several times stated at WWDC that it has no intention of preventing users from running code of their own choosing on macOS, rather than requiring all executables to be distributed through the App Store or notarized. Last week I looked at how Ventura checks apps and command tools now, and found no evidence that unnotarized executable code is put at any disadvantage, for example by checks that might delay its launch.

Under the security procedures built into Ventura 13.4, you’re free to choose from apps and tools that are:

• bundled by Apple in the SSV;
• supplied through the App Store;
• notarized by Apple and supplied by developers;
• signed ad hoc and built by friends, or yourself.

Although apps and tools that haven’t been notarized don’t benefit from the malware checks performed by Apple for the purposes of notarization, or Apple’s control over their ticket validity, they should still benefit from protection by Gatekeeper checks and provenance tracking. In circumstances where you don’t need the chain of trust provided by a developer certificate and independent malware checks, ad hoc signatures are better than nothing. They also ensure that Mac users can continue to run code of their own choosing.