It's not my main reason, but it's one of my reasons.
Nobody disputes historicity of Jesus nowadays for the most part, and those few who do are not serious scientists.
There are three possibilities to pick from when reading about Jesus. Only three:
1. Jesus was a con man,
2. Jesus was a crazy cultist, imagining to be son of God,
3. Jesus was who He said He was.
Historicity being confirmed, Jesus was not mythical concoction. There are no other options about who Jesus might have been, but these 3. Now, all that is left is to pick which one to believe. Can one really, with intellectual honesty, read the entire Gospels and say Jesus was a conman or a narcissist cult leader. For a reason, people were compelled immediately by Jesus' teaching, because he didn't talk like their priests, He knew people deeply and what was in them individually, and this showed. I felt very compelled by Jesus' words reading the Gospel. It's not how people talk, even wise spiritual people. Very very hard to read it and not believe Jesus to be who He said to be.