This is wrong on two points, based on the other discussion and the post itself.

There was no Telemetry outage. An HTTP3 response header’s case was changed by a third party without notice. Telemetry continued working, other than the case change causing a bug.

There was an http3 infinite loop bug in Firefox that crashed all networking. Many different things could have triggered the bug once it was introduced. Telemetry happened to be the first thing to do so, but not due to any faults in Telemetry’s code or implementation.