This says nothing about it being a canary. All canaries are stated as such.

Instead, all I see is some debate about PGP.

I can believe that only one submission ever used it. PGP is not friendly to people who barely undersrand how computers work (99.999% of the population), and some panicking whistleblower isn't interested in taking a layman's course in crypto to send some docs.

So why would wikileaks renew their useless(from their perspective) PGP key?