Board Thread:Theories and Speculation/@comment-34656247-20180531072459/@comment-33150793-20180601235817

There's no magic key to Uchiha blood allowing one to resist Tsukuyomi. Just that it's such a powerful genjutsu that usually only a Sharingan-using Uchiha should be able tor esist it as a general rule. Given the Rinnegan has explicitly shown able to resist the Infinite Tsukuyomi, it would seem there are always exceptions.

We've seen Hashirama is considered invincible even when Uchiha were plentiful with the Sharingan. We have it explicitly stated Hashirama is far stronger than any contemporary ninja, which includes Itachi (and are shown such explicitly). We have Hashirama able to, at near full power, easily able to break the control of Edotensei whenever he feels like it, something so powerful that only Kotoamatsukami could override it otherwise.

Everything here is speculation, but Hashirama is put on a different plane, someone who normal rules don't apply to.