A lot of the commonly used speed tests have a start or Go button.

This isn't bad behaviour, people just may not expect it based on what they are used to.

It's bad behavior if you're paying a lot for bandwidth…

I thought it was gonna be a public dashboard of transfer bandwidth globally in the cloudflare network, so domain could have been more descriptive. How about "speedtest.cloudflare.com"?

Not good. I didn't click on the link because I was worried it might, but I almost did.

If I had I would have probably brought at least one video conference to a halt.