Continuity. Standards and limitations keep the platform usable which makes it valuable to all involved. For walled gardens to be successful, both consumers and developers must both buy into them.

So, either people are painfully stupid or a managed platform has some appeal over free ones.

Continuity, ease of use, various warranties/guarantees make walled gardens attractive. If consumers have free reign and brick their device, it's hard to expect the manufacturer to have/honor any warranty. If developers have free reign there's no guarantee another application won't break theirs or that they won't break someone else's... or that it'll work with whatever the consumer is doing.

Yes, an obvious counter point is *nix systems, but there is some authority in that ecosystem which keeps most things working. It's still not painless to setup/use which prevents it from effectively competing with windows/Mac OS.

Simply put, the price of admission into a walled garden comes with some perks/guarantees/warranties which aren't readily available elsewhere.

Windows and Mac OS are not walled gardens in this way, although both Apple and Microsoft have shown signs of wanting to make them more so. Despite Windows not being a walled garden it has better continuity than any platform Nintendo has ever made, and ironically not only for Windows (and DOS) software but for most Nintendo platforms too via emulators.

Fair point, that was a poor example/counter example on my part.

What I had in mind was more a long the lines that windows/Mac OS isn't transparent and the consumer has limited control over what it's doing and how to implement things. Furthermore their official app stores are a walled garden of sorts.

Consumers/developers have a good deal of freedom on these platforms and with that comes breakage in various forms. Malware, instability, etc. And to deal with that you have repair shops/programs. System resets, fresh installs etc. Maintenance becomes a responsiblity of the consumer.

Like I said, the lines can move based on context. Moving the needle further towards freedom for developers/consumers gets you *nix systems - which is harder for your average consumer to maintain/use. Moving away gets you iphones/consoles, etc which "just work" and flaws in software/hardware handled by the manufacturer.