It's a shame that A) Bird's back problems cut his career short and B) Bias/Lewis passed. Those two almost definitely would've give Bird another shot at a ring, perhaps multiple rings, like Kawhi and now LMA are doing for Duncan.
Regardless, the idea that it's preposterous that anyone could have LBJ over Bird is, well, preposterous. I wouldn't doubt it'd be a heck of a match up between the two in their primes, but I think at the end of the day, barring injury, LBJ's longevity will make him the greatest SF of all time.