Board Thread:Boruto Discussions/@comment-38812954-20190920230637/@comment-38812954-20190923105725

It's what had to be summoned^. If you apply the concepts of the summoning jutsu when it was first showed. Your level of chakra determines exactly what you are capable of summoning. Naruto and gamabunta for example vs all his previous toad summoning without kurama's chakra. All the tailed beasts Kakashi, Sakura and particularly Naruto and sasuke had to be summoned back to their right dimension. Even though it's suprising that Hagoromo couldn't do it himself (and kinda still not suprising as i'll explain) a lot of chakra was required for this particularly because of the tailed beasts and maybe Naruto and sasuke who's chakras are also large. It's basically like Hagoromo trying to summon himself and his creations back to a certain place. With absolutely none of them being under contract and having chakras so large (Sakura and Kakashi exception). If you compare that to sasuke summoning a hawk in another dimension. Especially having half of Hagoromo's chakra plus rinnegan. You could totally understand why. A feat like that would be too easy because his power is off the charts in that particular case.