While attempting to use the [1.1.1.1 DNS service provided by Cloudflare](https://one.one.one.one/) on my home network, all queries timed out. I am a CenturyLink fibre (now renamed Quantum Fiber) customer. Why?

Use here means adding it as an explicit DNS resolver in a Mac, a Windows 10 PC and in a linux server running using DNSMasq as a DNS Forwarder.