The law could never save us, so teaching us the law was not the purpose of His incarnation. His death paid the penalty for what we deserved for all who believe. His resurrection assures believers of eternal union with Him. You cannot be deemed righteous in God's eyes by observing the law.
What if Pilate had spared him?
There would have been no crucifixion, and Jesus would have died of old age, in his bed.
I think that he was not meant to be crucified. He came to teach us Love.
and we are supposed to love mankind as much as he did.
that's the meaning of his coming