[joshuamorton]

A lot of them are related to Google-internal practices or libraries, or are like too opinionated (Google has strong internal C++ opinions that aren't necessarily correct or even reasonable elsewhere) to be useful.

110 in particular probably could be public, but it looks like they stopped externalizing them in late 2020, which is kind of sad, so I assume they never got around to it.

[jrockway]

Yeah, that sounds about right to me. I used to help edit Testing on the Toilet and there were a lot of internal-tool-specific ones that we never made public. When we were low on content, we would happily publish an issue about someone's internal service/project, for example. It's not that we were trying to hide something, it would just be completely useless to the outside world.

[Thorrez]

TIL TotT is externalized.

https://testing.googleblog.com/