Board Thread:Boruto Discussions/@comment-38812954-20190920230637/@comment-1210805-20190923101408

The only other example we have of a cross dimensional summoning took the power of all previous Kage and Hagoromo. Granted there wasn't an existing contract but to assume just anyone can summon something in the same circumstances as the Sasuke example is to ignore all the other factors at play at the time.