[permo-w]

I agree that the downsides outweigh the positives, but they do provide security to a certain extent.

For example, you can give your grandma an iPad or a chromebook, and there’s very little chance of her accidentally installing x nasty malware.

Give her a proper laptop, and at any one time she’s about 6 clicks from something dodgy, especially if she’s on social media.

[egocentric]

That's because of system-level protections like the sandbox, not App Review or the App Store.

[permo-w]

yes but if you allow alternative app stores, then what? it’s either regulated by apple, which defeats the point, or it’s a security risk.

I’m against walled gardens, I just disagree that there’s no security upside to it

[Barrin92]

put a system setting in place that lets you lock down the device if necessary with a password so grandma can use it safely?

As OP points out you do not need an app store monopoly, you just need adjustable device settings.