Juubi is the combination of all Bijuu, how can one be a juubi Jin without sealing the Juubi? He had all 9 beasts, did you miss the part where the Alliance pulled them all out of Obito?
And did you miss the part where Madara captured them all again?
If Madara has all 9 and it puts him at juubi jin level, obito has all 9 and it puts him at juubi jin, then same goes for Naruto, he has all 9, thus juubi jin level.
yea, but this isn't the extent of his ability. all we have seen is what he needed to get there quick enough and kick the gudou dama. when he legit activated his abilities, it's gonna be awesome. hopefully madara actually fights back.