Barnes was bitchy in the 60s and 70s because as the chief critic for the Times, he could be.
"Legendary"? Since when?
When Rupert Murdoch at the Post gave him a heap of money and also gave him his job of chief drama critic back (the Times had 'demoted' him to just chief dance critic) as well as chief dance critic, the quality of his work began a long slow slide.
He was grossly overweight, had a rep for drinking and also for sleeping.
And this has been my personal curiousity for about 20 years: could Barnes be bought? I mean quite literally, with money or more likely the promise of a big ad in the Post in exchange for a favorable quotable review?
I know I am not alone thinking along these lines.
Barnes devolved into a slob.
"If my life weren't funny, it would just be true. And that would be unacceptable."
--Carrie Fisher