The Romans weren’t trying to kill all the Jews, but they did destroy Jewish resistance to Roman rule. Jerusalem was turned into a Roman army camp, and it was a total devastation.
What survived as orthodox Christianity did so by suppressing and forcibly eliminating a lot of other material.
The Antichrist is often identified with the second beast in the Book of Revelation that arises from the land, the beast that tries to make everyone worship the power of evil.
The Secret Revelation of John opens, again, in crisis. The disciple John, grieving Jesus’ death, is walking toward the temple when he meets a Pharisee who mocks him for having been deceived by a false messiah. These taunts echoed John’s own fear and doubt.
There are some kinds of Christianity that insist you have to believe literally in doctrine. The Gnostic gospels open out the complexity and multiplicity of approaches to this. If you think the story of the virgin birth is mistranslated, for instance, it doesn’t mean you have to throw out the whole thing.