The Uzumaki are basically the clan of doing what others would think impossible. Mito-sama was the first jinchuuriki? Who else but an Uzumaki would look at a giant ball of rage and chakra point at it and be like, “Yup, gonna contain that with my mortal body. What could possibly go wrong?” (Surprisingly little, actually).
The summon realm is, like many things in canon Naruto, a fascinating idea that never got explored much to everyone’s frustration. How does it work, Kishimoto? We will never know.
I’m hoping SQ touches on it one way or another, because I have no doubt she can do it justice. But there are plenty of other areas that direly need world building and those more relevant to the plot as well. Maybe she will, but it probably won’t be via DoS–maybe one of the Sunshine Sidestories or a Reincarnation Roulette chapter…