It is relevant: Apple's system is closed against meddling by lazy middlevendors as well as against the likes of us. If Apple decides that you should upgrade (or not) there's little Deutsche Telekom or Verizon or any other middlevendor can do about it.

That it's closed against us is not nice at all, but being closed against Deutsche Telekom and Verizon and such is a feature, not a bug.