Comment by eastdakota

Typically, if you experience that, it’s because DNSSEC fails. 1.1.1.1 enforces DNSSEC. As does 8.8.8.8 in most, but not all, cases. Many other DNS resolvers do not enforce DNSSEC. Archive.is (and its directly affiliated sites) are the only exception like this I am aware of. And, to be clear, as a policy the 1.1.1.1 DNS does not block any sites from resolution.