And because a Jin can focus the Bijuu's power, as shown with Obito and the Juubi. Inb4 you say it was because its the Juubi, no, that was never implied. B doesn't need to bring anything new to the table when he's just stronger all around.
Not to mention even the bold would factor in this fight.
You're probably right, but i'd like a better explanation.
Bee's BM is no different that Gyuki's form, the 3rd would be fighting the same thing (physically). Also, Gyuki didn't manage to actually harm the 3rd, the later died because of a mistake. Ultimately, Bee's weapons are Gyuki's weapons, which didn't work.
What does focused power actually means and how would it play a role?
When i claimed PJ are better, i meant it in a profitable way, for the village. This would only be a factor if there's intel on Bee's side (which there is since the op didn't specified, so i assume its manga intel, therefore Bee would win; i guess i didn't think this match properly the first time).