I think the strongest argument in his favor there is that he played on one of the best teams of all time (86, in case anyone who's not all that stoked on C's history is reading), so those assists would, in theory, be fairly easy to come by, particularly because of the way the team played anyway.
OTOH, he didn't, you know, do it. You could just as easily say that you bet Kobe (or Jordan) could've broken Wilt's record, too -- Although Bird was much closer to the Averaged Triple Double than those two.