I don't understand why anybody would consider to be at risk if an alternate store, that nobody would be forced to use, and which could even be subject to identical or even better rules, exists.
And I'm not even talking about transforming an iPhone into a potentially open computer, but here too the same principle can be applied: if it is optional, it is something more, not less. The UX can be made good enough to actually have your cake and eat it, see Chromebooks.