I fully understand (and share) your aversion to personality cults. And it's definitely possible that there exists some actual personality cult/fandom around Carmack.
BUT - I strongly believe, that he has earned quite some respect during his career.
And - importantly in this case - he is well known for NOT blowing things out of proportion, indulge in wishful thinking, hyping up unrealistic expectations or jumping to premature conclusions. He usually knows what he's talking about.
This is not people blindly believing everything he says - but more a case of his statements holding up really well under critical inspection most of the time.
BUT - I strongly believe, that he has earned quite some respect during his career.
And - importantly in this case - he is well known for NOT blowing things out of proportion, indulge in wishful thinking, hyping up unrealistic expectations or jumping to premature conclusions. He usually knows what he's talking about.
This is not people blindly believing everything he says - but more a case of his statements holding up really well under critical inspection most of the time.