The point is not whether Jesus was real or not (although there are some who claim that he wasn't). Mithras is believed to have been real as well. The other two were admittedly gods, who may not have existed in real life. Of course, Confucius and Buddha were said to have been born of virgins also.
The problem as I see it with Jesus is not that he wasn't real. I am prepared to concede that he was. But everything about him was mythologised. Jesus of Nazareth was in fact a Jewish Rabbi, of the Pharisaic tradition, which is why he could criticise them so well. That he was a Pharisee is proved by the fact that he believed the entire Jewish Scriptures (the Saducees accepted only the Torah), he believed in resurrection (the Saducees didn't), He believed in angels and demons (the Saducees did not), he believed in the Afterlife (the Saducees did not), he taught in parables (which was a common way that Pharisees taught), and that he spent a considerable amount of time in synagogues (the Saducees were intimately connected with Temple worship).
So this Jewish Rabbi had his life mythologised with all that virgin birth business, and the whole dying and rising saving God business. And Christianity instituted baptism, mirroring a rite of many of the Eastern Mystery Cults, including Mithraism, and Communion, also mirroring Eastern Mystery Cults. Check any good encyclopedia under the headings "communion" and "baptism".
So this Jewish Rabbi who was nailed to a cross for pissing off the Romans turned into a deity. Go figure. Furthermore, the whole Passion narrative is nonsense.
According to the NT, Jesus was brought before the Sanhedrin at night. Except that the Sanhedrin never met at night. He was condemned by about fifteen people. Except that the Sanhedrin never met with less than a quorum of 71. And he was convicted of violating Jewish law and then given to the Romans. Except that that was unnecessary. The Jews had the prerogative of executing violators of Jewish law by stoning. All they had to do was get the consent of the Roman governor, which consent was rarely denied. So the whole idea of Jesus being punished by the Jews is idiocy.
The whole game is up. These are the reasons that Jews have never converted to Christianity, with the exception of those who usually haven't known their own religion very well in the first place.