I was going to say: Gnunet pet names aren't globally unique, therefore Gnunet gives up on having the human-meaningful addresses be globally unique. However, from your link it appears that there is no requirement in Zooko's Triangle for those human-meaningful addresses to be globally unique. So it doesn't actually give up anything:

1. Pet names are human meaningful (though not globally unique). Check.

2. Public keys are secure (and in the typical cases globally unique, btw). Check.

3. Gnunet zones are decentralized. Check.

There you go. Triangle drawn.

AFAICT Gnunet punts the names down to the user in a similar way to how Convergence punted CA choice down to the user. In both cases the user chooses which entity or entities to trust, being more or less strict in what to do if those entities disagree based on some predetermined criteria.

In reality, however, I remember that Google balked at adopting Convergence because it seemed likely that most would have eventually just standardized on delegating their own choice of "decentralized" CA to Google. Then you'd end up with an ostensible decentralized set of authorities where that set is simply { Google } for the vast majority of users.

I don't see any mechanism in Gnunet that would avoid a similar fate. Especially given that the examples given in the current docs are so goddamned confusing and convoluted that a tempting workaround would be "Step 1. Just set Google as your thingy." I offer into evidence exhibit one: Gmail.