It happened enough times that I'm suspicious the ISP had some way to detect if you run a speedtest, and then prioritized traffic to that customer.
That said, why didn't Netflix acquire the market leader in this space? Creating their own seems way less useful, since network effects are the whole point.
ISPs definitely know when you run a speedtest.net test. 90% of the time, the data for that comes from boxes/services they host themselves. It’s not exactly hidden either. It’s a typical program any ISP can sign up for and you can easily see the destination the test is running against. I won’t be surprised if some have some logic to prioritize particular subscribers plan once they have detected a test from them. They probably view it as a “customer support calls reduction” feature.
Yeah, I suspect you could script it to do it daily. They definitely seem to deprioritize traffic from people that don't complain.