Don't think you can compare those two, as they are different things. Even if Cloudflare "relies more on their own infrastructure", they still have to have peering agreements with others, otherwise they can't accept/send traffic.

More likely, Netflix has better infrastructure and better peering agreements, than Cloudflare. Which is kind of surprising, since Netflix is supposedly a media company and Cloudflare is a "internet" company.

Netflix has an advantage: their OCA boxes may handle speed test traffic [1]. That means a box racked at your ISP[2] may be serving that traffic. While Cloudflare may have nice peering agreements, they don't have that.

[1]: https://netflixtechblog.com/building-fast-com-4857fe0f8adb

[2]: https://openconnect.netflix.com/en/#what-is-open-connect

How does that explain me getting solid results from DSL Reports, Ookla to a random server I picked in Ashburn, and to Google Fiber's servers in Atlanta, Charlotte, and locally.

I think there's something about the methodology of Cloudflare's test.

My point is limited to "fast.com could give faster results because you may not even leave your ISP to talk to them"; I'm not here to say "Cloudflare's results are good/bad/better/worse/reliable/unreliable."

A thought, though: Cloudflare reports your p90 time as "your speed". I don't know what the other sites report. Is it the same?

Or the ISPs don't throttle traffic to fast.com

That makes sense, think there been evidence of ISPs throttling connections, except for speedtests, in the past, so would make sense. My own ISP also used to throttle Steam downloads for a couple of years, until suddenly they didn't.

I thought one of the goals of fast.com was to let users find out if their ISP is throttling Netflix. ISPs can't only throttle a speedtest if Netflix makes it indistinguishable.

Maybe that is, but one can think of a number of ways for ISPs to work around that. Quick thought: if the ISP is also your DNS resolver (which is the default for most people), check if there been a query for fast.com and if so, stop the throttling for five minutes. After those minutes, start throttling again.

Not so, Viasat will throttle based on headers and even built helpers for speed tests that bypass other limits. Such as forced video resolution down grades.

I thought Cloudflare also peered caching servers?