Some people say it was inconsistent but I don't think so. Kaguya wasn't as physically strong as the other juubi kind, who were actually using the Juubi's power to mutate their bodies and increase their strength stat. Kaguya is different, she controls the chakra because it's hers but she isn't a jinchuriki of it she IS it. Her princess form is not physically strong it's just fast and nimble but fragile and physically weak like a glass cannon. Her arm can be torn off by a strong enough character with ease Naruto couldn't do that too Madara. She can be punched by Sakura, she can be brought to her knees by the same gravity as Sasuke or Kakashi. She doesn't punch people with her girly arms, she uses chakra fists instead for blunt offense and defense, her chakra and bones are her forms of battle but her body itself is fragile however it can absorb chakra and ninjutsu as well as regenerate after a bit if destroyed. Naruto isn't as physically strong as the Juubi jins either and mostly on par with Kaguya but considerably stronger still, especially when he boils his chakra or uses it to dilate his speed of force.