People say that Kirin is going to be used against Obito, and I can see that most likely it won't simply because it isn't practical.
It takes a great deal of set up and you only get one shot with it.
Why would they waste time and chakra to set up a single attack that may or may not work, and Obito isn't going to sit around and let them set up an attack.
They already have a way of fighting Obito using Sage Mode, and they can use it multiple times with minimal set up.
It would be illogical to throw away a working strategy for one that they can only use once, if Kirin doesn't work or is blocked or misses then they have just burned a lot of chakra and time for nothing at all while with Sage Mode they can attack multiple times with little prep.
There is no reason for Sasuke to even bother bringing up Kirin.
It takes a great deal of set up and you only get one shot with it.
Why would they waste time and chakra to set up a single attack that may or may not work, and Obito isn't going to sit around and let them set up an attack.
They already have a way of fighting Obito using Sage Mode, and they can use it multiple times with minimal set up.
It would be illogical to throw away a working strategy for one that they can only use once, if Kirin doesn't work or is blocked or misses then they have just burned a lot of chakra and time for nothing at all while with Sage Mode they can attack multiple times with little prep.
There is no reason for Sasuke to even bother bringing up Kirin.