Telemetry should be able to be switched off entirely, on all Windows installs, so that our right to privacy in respected. Many of the apps that I use include telemetry but I only use those that provide an option to disable their telemetry, even though I will allow telemetry from some trusted apps. MS have repeated demonstrated that they cannot be trusted and it is scary that the released an entire OS that is actually spyware. In any case, it means that Windows 7 will be the last version I allow to be installed on any computer I own.
If Windows update doesn't work without telemetry, that is a demonstration of MS incompetence and a very bad design decision. Linux is my main OS and it sends no telemetry for updates, while still managing to install updates. Those Linux updates also cover every piece of software I have installed in that OS, not just OS updates.