No offense OP but doesn’t that seem a bit too easy. I mean after all he (Jesus) preached about love thu neighbors, turn the other cheek and all that to just die on the cross for everyone in the future to simply ask for forgiveness. Remember you are saying that Hitler, Stalin, Mao, child murders and the like simply need to repent and believe on their death bed and bingo your forgiven.

I think more likely he came to tell humanity about the morals of god. That if you live a good life and treat everyone with kindness, love and forgiveness even those who have wronged you. Then you will be accepted in his kingdom. His sacrifice on the cross was for those who came before him. Those who did not have a chance to hear his message.

Just a thought