Specifically it states: " The software (including Boot ROM code, embedded software and third party software), documentation, interfaces, content, fonts and any data that came with your iOS Device (“Original iOS Software”), as may be updated or replaced by feature enhancements, software updates or system restore software provided by Apple (“iOS Software Updates”), whether in read only memory, on any other media or in any other form (the Original iOS Software and iOS Software Updates are collectively referred to as the “iOS Software”) are licensed, not sold, to you by Apple Inc. (“Apple”) for use only under the terms of this License. Apple and its licensors retain ownership of the iOS Software itself and reserve all rights not expressly granted to you."
If a person has agreed to these terms, I don't see how they can complain about Apple's policies in the future. The same software that isn't owned by the person, but is Apple's, now refuses to run Steam Link. The person who agreed to such terms had it coming, you can't blame Apple for that.