It's as simple as that. The Son of God Himself said that He was the Way, the Truth and the Life, and that apart from placing faith in Him, no man could get to the Father. If we could be saved by Judaism, Messiah Yeshua wouldn't have said to a Jewish man like Nicodemus that it wasn't enough to be born once, even if one was a knowledgeable or pious rabbi . Pretending the dying patient isn't sick doesn't help the patient. Acknowledging that he is sick, and then administering the appropriate medicine is what the dying patient needs.
Ignorance is no excuse.
We are responsible for the information given to us through Moses and the prophets. We have the revealed Word of God, written by our own Jewish prophets, which clearly points us to Yeshua. The one who accuses you is Moses, in whom you have set your hope. I never knew. Besides, my rabbi told me not to believe in Him, so it's not my fault.