That is true but Naruto has Kyubi hax healing, if he can survive a Chidori to the lungs, he can survive a sword stab.
Sasuke was outpacing Shin, Sasuke has always been the type to use strategy in his fights when he isn't going batshit crazy, so him using Amenotejikara+Fireball was expected, the fight wasn't long, but it was enough to clearly show the difference in skill between the two. Again, had it been 1v1 the fight would've been over with the Fireball. Nothing was stopping Sasuke from simply repeating what he did before with the fireball besides, oh yeah, the knives headed towards Sarada. Sasuke could've simply been stunned, not paralyzed.