That link shows empty to me, since I've never logged into YouTube, and most of the time I'm not even logged into the Google account.

(I don't know if it's still the case, but I've heard that if you log into YouTube, and Google for some reason decides your real name is not your real name, you could lose access to your whole Google account; and at least to me, the Google Talk account was more important than being able to comment on YouTube videos.)

I don't think that's been a thing for a long time.

https://en.wikipedia.org/wiki/Nymwars

Last I checked, it was impossible to create a YT/Google account without providing a (working) phone number. Which is even worse than requiring "real names" (which can at least be spoofed).

That depends. I’ve found that, while creating an account on an iOS device, providing a phone number isn’t required, but while creating an account via a desktop browser, it is.

It will probably depend on other factors as well such as IP, country, …

It was still possible as of six months or so ago, who knows what factors Google takes into account to decide whether to require a phone number or a simple email.

The absolute future of a proprietary service-specific history.

That would require to be logged in to a Google account

Does it work when a video was deleted?