When you don't know who runs archive.is, you can also never know if he sold it to someone else (except if either party publically announces it).

This type of possibility really worries me. Archive.is is much closer to actual history in many ways. If the data there starts getting corrupted or biased, there’s no way to know if what was truly there.

The idea that the permanent record of the internet could hinge on the ethics of one stranger behind a server rack is deeply unsettling.

This happens on .gov websites a lot now, and it is deeply unsettling.

Knowing the current owner of archive.is doesn't help; we need more full, independent Internet mirrors that can be compared against each other.

Archive.is does not archive the page exactly as is.

And when the information on archive.is starts getting corrupted, those links can be adjusted or removed.

Who will catch it, when and how?

I never said there are examples. However, "who you are" matters, even if you don't care. At least when the who is known, we can guage the trustworthiness and what bias exists, because there's always a bias. When who is not known, you don't know what bias to account for. That's not trustworthy and not reliable. And when the site is closed source and you have no idea how it's being run, nor by whom, you don't know "what you do" either.