The person you're replying to is clearly aware of search ranking algorithms. You should try looking into the HITS algorithm they mentioned for some additional context.
It had been applied decades before through scientific paper references, as a measure to improve on the "number of references" metric, which is more easily gamed. References are more rarely circular (only same time in-preparations can form cycles, unlike web pages). I was sitting in a class about stationary processes in 1996 when the lecturer mentioned this (already old and well known at the time) use case as motivation.
Whatever AV implemented at the time, it was not on par.
Pagerank is essentially a “universal authority score” (in the HITS terminology), and it worked well because at the tine you didn’t have pages that were authority for one subject and spam for another. You do now - which is why pagerank is now one signal out of 200, even though it was sufficient on its own 20 years ago.