CDNs have existed since the 90s so everyone's had time to get used to it. The part which I think you're over-weighting is that this is not a third-party stranger but a third-party with whom you have a legal relationship — the use-cases for a CDN require external termination, otherwise you don't rent one, and the contracts commit to keeping it secure.
For a business, there are tons of trust relationships you handle this way: you trust Microsoft not to ship a trojan in Windows, Cisco/Juniper/etc. not to sniff your internal network traffic, Google not to ship your Chrome session keys back home, etc.
a) it was one of multiple examples
b) do you personally run a business this way and, if so, how's that working out relative to the competition? My point was simply that all businesses have some parties they trust on the theory that they'll sue if a contractual agreement is broken. It's too expensive not to trust someone when you have no reasonable basis for expecting an attack and a solid legal basis for compensation if they did: if you dislike Microsoft, substitute Apple or Samsung, your bank, etc.
Please enlighten me on what that term means.
Because All the telemetry/cortana does is disguise itself as a useful feature , while collecting user data and siphoning it off to its central servers.
For a business, there are tons of trust relationships you handle this way: you trust Microsoft not to ship a trojan in Windows, Cisco/Juniper/etc. not to sniff your internal network traffic, Google not to ship your Chrome session keys back home, etc.