Interesting read on the probable owner of the site : https://webapps.stackexchange.com/a/149405
If archive.is hosts content that has been removed due to oppressive regimes' policies (including western ones), exposing their identity may put them at risk.
For example @volth on Github - as a person - is still around in other places, so I'm guessing that account was stolen and they don't have a way to get it back.