Reason why Sasuke waited until now...

[Mellanoma]

While true, remember what happened last time everyone said this about Sakura and Kakashi when team 7 was fighting kaguya. You never never know what role they will play. Though i doubt either of them will interefere with this fight. They know as well as Naruto and Sasuke, that this fight ws going to happen eventually. They will probably just spectate this time.

True Kakashi got a Obito powerup and Sakura got her boost... This time though there is no more magical powerups as everyone is dead fully or in IT

Sakura and Kakashi being there will make it difficult for naruto to fight this is why they won't interfere

There only possible help and aid is to cheer Naruto on from afar and stay out of his way considering Sasuke is known to use others as a means to victory and Naruto is known to start losing a fight to try and protect others

 

[salamander uchiha]

Narutos greates weakness is genjustu especially uchiha genjutsu.
The only reason hed wait is because they had to beat kaguya then he needs nardo to wake up the rest of them otherwise he would have solod him with a chibaku tensei.

 

[WalksInShadows]

I highly doubt that's the only reason he waited.

actually Sasuke says he was just then getting used to it, so yeah, that was pretty much it.

Pretty much. He knows the only one that has a big chance of defeating him is Naruto, and with no one being in the way because of IT, he found this as a perfect opportunity to take him out as well as any other possible opposition.

hate to burst your bubble, but Sasuke mentioned Madara and Kaguya as being on the list of threats to his agenda before getting to Naruto. He pretty much confirmed Madara and Kaguya would've ended him.

 

[ColdSummer]

Your just about right on why he waited till now, but Sasuke won't kill Naruto. They need to work together to undo IT

According to the mangapanda translation, the Sage stated that Sasuke's Rinnegan and the beasts' chakras were needed to undo IT. Sasuke has the tailed beasts under his control and trapped due to Chibaku Tensei. Technically, he doesn't need Naruto to undo the technique at this point.

 

[DeadManWonderLand]

All that was obvious

Also orochimaru and kabuto knew more then anyone
They deciphered almost the entire tablet without the dojustu and orochimaru always stuidedor capturedanyone related to the sages blood line