The firm has become a vocal opponent of what it views as UK government moves against online privacy
This is a huge understatement. People already view online privacy as non existent, so they won't be very concerned with the implications. This goes well beyond online privacy. iMessage and Facetime are used for the majority of iPhone user's communication with friends and family. This isn't very different than the government planting a listening device in your living room and monitoring all of the conversations you have in your house. This isn't a violation of "online privacy". This is an intrusion into people's basic essential right to privacy, period.
Makes sense. Apple has tied their corporate identity pretty closely to protecting personal privacy and they’ve also set up E2E encryption of iCloud pretty recently (end of last year). Probably just easier to turn off those communication options then to try and deliberately punch holes in the protections they’ve set up.