Quite. For example, in the case of the Stanford incident, in the last century there have been maybe two major biographies of Stanford and about thirty of Elgar (a complete guess, sorry). The Elgar biographies all give the impression that Stanford offended Elgar within a few months of them meeting, and that they never really got on, whereas according to Jeremy Dibble's biography of Stanford, the two were good friends for something like eight years, and the Stanfords came to stay with the Elgars. And it is also no excuse for dismissing Stanford's music. Stanford was, admittedly, quite good at falling out with people, even Parry had enough of him in the end, but who cares? I doubt I'd have liked Wagner or Brahms much as people, but I'm happy to listen to them.