I do agree that the problem of developers and apps being affected would be a huge problem, which would be the only problem I can think of. Developers do like the ease of mind of being able to target one platform (for the most part), one system, etc.
I still think the disclosure agreement would take care of that though. Users would have to be notified and made aware that they could potentially lose apps working (it would still be a nightmare for developers though). I guess I never thought of that because when I updated to iOS 11, none of my apps needed to be configured or anything like that (and I was on the early betas). Everything worked just fine after I had updated, but that is just in my case...
I still think the disclosure agreement would take care of that though. Users would have to be notified and made aware that they could potentially lose apps working (it would still be a nightmare for developers though). I guess I never thought of that because when I updated to iOS 11, none of my apps needed to be configured or anything like that (and I was on the early betas). Everything worked just fine after I had updated, but that is just in my case...