(And don't even get me started on how Apple readily removes access to apps after demands from Putin's Government.)
On the other hand, as a user, and one who has to do de facto IT support for my family, I strongly disagree. Having an off-store method of installing apps is just dangerous. You could argue that it's a question of Apple having an incomplete security model, in which they enforce through human review that apps do not perform malicious behavior. But Apple is just pretty good at this -- the rare app that slips through their net is usually quickly caught and killed, and their security on-first-use opt-ins "Allow this app to access your camera", along with enforcing that apps for whom the permission is denied must still function, is critical, compared to the Android "Allow this app to access all device state forever including private information and your entire DNA sequence" that you get on app install.
On the gripping hand, advanced users, like developers, can basically sideload whatever the hell they want. The barrier here is a lot stronger than a checkbox in settings saying "allow sideloading apps" and thus is intrisically more difficult to access, and then only by people who know what they're doing anyway.
I can't help but find this to be extremely infantilizing. The whole point of a democratic society is that we believe that we can educate people rather than relying on some authoritarian dictator to decide the limits of our freedoms. What you appear to be suggesting that your family is too stupid to be educated? Are you sure about that?
But I am not suggesting that my family is too stupid -- rather, that the level of expertise required to safely determine whether a given app is safe to sideload is not only beyond the reach of a casual user, it's beyond the reach even of an experienced expert. Is my family too stupid to understand quantum field theory? I don't know -- maybe? Does the framing of "too stupid" make sense with that question?
Maybe someday we'll have sufficient app isolation that there will be no worries about the idea of running completely untrusted native-code apps on your device. But this is not that day.
To sideload on iOS via the developer tools you need a Mac, and the builds will expire. So it’s not a viable alternative to sideloading due to the cost and inconvenience.
A checkbox that says "I understand the risks involved" is never going to cut it, because there is 1) no way that the overwhelming majority of users understand the risk, and 2) the existence of the option puts us in a world where completely naive users are told "to install the cat-picture-a-day app, first click the 'allow sideloading' button and ignore the warnings, and then go to cat-picture-a-day.ru and install!"
As the article notes, we saw this with malware and browser toolbars in the 90s, and we see it now with misbehaving sideloaded Android apps (and "repurposed" Android apps). I personally am happy to pay the premium to get a quality device that forces developers into a constrained environment for my benefit.
I too like the walled garden. I don't really see that as an argument against sideloading however. Presumably the first-party app store would continue to operate with the same restrictions and I'd happily avoid opting-in to sideloading.
The people who want it are happy and I'm no worse off.
The App Store is a forcing function for app developers, because it's the only way to reach IOS customers. Without that forcing function, some app developers will circumvent, and if a critical mass does it, then you no longer have the option of opting out.
Apple can presumably make the warnings scary enough to make app developers reluctant to leave, but alternative less restrictive app stores and big-name developers will lobby to have those warnings removed for being deceptive.
Apple should not have that kind of power over owners of the devices Apple manufactures.
If some game announced you could only get it through an alternative app store, I wouldn’t play that game.
Banking is critical functionality on the other hand. Under those circumstances, I’d change banks. The likelihood of any major bank attempting that seems awfully low and I’m sure it’d attract the widespread condemnation it deserves.
Android has sideloading. I don’t doubt some apps try to push users to an alternative marketplace but important everyday apps are where you’d expect them to be.
Others should be able to use their devices as they please.
Also, the argument that 'you knew what kind of device you were buying' doesn't work, because Apple has shown time and again that whatever app is available at the moment of the purchase of the app can be later removed from Appstore by Apple for whatever reasons.
On the other hand, I think it’s reasonable to suggest that greater interoperability could result in some features being degraded or unavailable (maybe certain things happen slower, or consume more battery life, for example). We might still decide this is worth it overall, but it could genuinely handicap the UX.