Three operating differences between motorcycle chains and bicycle chains, not counting the O-ring seals on many motorcycle chains.
1- motorcycle chains run hotter
2- motorcycle chains run faster
3- motorcycle chains run in a fixed length closed loop, as opposed to the lightly spring idlers on a derailleur bicycle.
All three make a difference in optimizing a chain lube. That's not to say that MC lube wouldn't work on bicycles, just not as well as one balanced to the specific needs of a bicycle chain.
BTW- don't think that there's one perfect answer in the motorcycle world, any more than in the bicycle world. Motorcycle riders have the same quasi-religious debates about best chain lube as we do.