I doubt that your conclusion is correct (because local DNS resolvers that consult blocklists are often surprisingly slow) but I think your theory of the matter is accurate. The raw speed of the DNS server is almost irrelevant because there are other much larger systemic performance issues at stake. For example Cloudflare does not forward EDNS to the origin, so the records it returns are suboptimal for services that use DNS-based service affinity. It doesn't make a difference to me if Cloudflare is a few microseconds faster — and by the way I sincerely doubt that this python program is observing meaningful microsecond-scale differences — because overall it makes applications slower.

Fair points — blocklist‑based local resolvers can indeed be slower, and raw speed alone doesn’t capture the bigger systemic issues. The tool isn’t trying to measure microsecond‑scale differences, but rather provide a clear comparison of resolver behavior under load and over time. Things like EDNS handling and service affinity are exactly the kind of deeper characteristics that benchmarking can help surface, so users can decide which trade‑offs matter most for their environment.