Agree. Other comments raise the point of “what if Windows decided to do this... is it okay because Linux exists?” and the answer is clearly no. I bought an iPhone with the expectation that I would be in a closed ecosystem; if win10 updated to mirror win8 RT where you could only use the windows store, that would obviously be a problem because win10 users purchased a license with the expectation that they could install whatever they wanted on it.

> I don’t want to have to think about my phone that much, but I want to be able to rely on it.

I’m in the exact same boat; I have no interest in sideloading every app that decides to get into a pissing match with Apple (and as Spotify’s hinted at it before, they will certainly be losing my subscription if I need to sideload their app). For every app that has a legitimate reason to sideload (i.e. payments), there will be another app that sideloads to bypass the user-beneficial aspects of the App Store (i.e. Onavo from Facebook).