Providing backwards compatibility for decades has some serious tradeoffs. Breaking apps that were using the most up-to-date APIs three months ago is simply amateurish.
It's clear that Apple has no respect for developers on their platform.
As mentioned in other comments, it's very unusual for undeprecated APIs in iOS to break badly from one release to the next, at least the time I've developed for the platform. Usually if something is that broken it's because the app in question was using an API that was deprecated years ago despite repeated warnings.
