There's Ehrmann on the other side who claims that the evidence is solid that Jesus did exist, so it's not like non-believers all agree.
However, for me personally, the myth hypothesis makes more sense, and more accurately describes why the New Testament is so weird. Looking at the Epistles of Paul and reading them as if Paul were talking about Christ in a heavenly realm instead of Earth, it's a remarkable exercise. It works. I wouldn't expect any devout Christian to even be able to have the mindset to do such an exercise, as religious presupposition is so strong. But if you're ever able to do it objectively it's eye opening.
It perfectly explains why Paul, in writing over 100,000 words about Christianity, didn't once mention anything about the Virgin Birth, Mary, Joseph, John the Baptist, Christ's miracles, Jesus' ministry, Palm Sunday, Pontius Pilate, the Jewish Mob, nor does Paul even quote anything Jesus is supposed to have said.
The Christ myth theory, coupled together with the 100% proved fact that the Epistles came first, and the historical fiction gospels coming second, is the best explanation in my opinion.
I think many of the "majority of scholars" are presupposed to believe in the historical Jesus, and perhaps unaware of the evidence or think it unimportant.
...why the claims of Christianity arose from Jerusalem/Judea at the very time that the hostile witnesses were there to refute the claims?
Well, the Gospels were written around 70 or after, so it's highly doubtful that there were many "eyewitnesses" around to debunk the claims. It's likely that early Christians viewed the Gospels for what they were; a reinterpretation of history putting Jesus in middle of it, much like other people in the same era believed in other resurrection myths. There were all sorts of resurrection cults that combined Hellenism with other cultural myths, and Christianity just happened to be one that combined Hellenism and Judaism.
No one can say for sure, but I don't see any reason to believe that the explanation for all of this is that this ONE religion is actually true, and that the laws of nature were violated. You wouldn't accept this incredibly poor standard of evidence for anything not related to your religion.
Nothing that you’ve said explains the Christian symbols on the Temple priests’ ossuaries, why the contemporaneous Jewish writings say that Jesus was condemned for being a “sorceror” (one who performs certifiably-real miracles, supposedly using the devil’s power) and why they ridiculed the idea of a man also being God or someone rising from the dead, why there were enough Christians in Rome within a couple decades that Tacitus mentioned them specifically, why Luke supposedly writing so much later gets the science/geography/nomenclature right even when the reference materials at the time didn’t, why the non-pastoral Pauline Epistles which are compiled and contained in an actual physical codex dating to around 80CE contain references to the same events that are claimed in the Gospels, etc.
You’re going to believe what you want to believe. That’s fine. It’s your life.
But there are a lot of good reasons to believe the opposite of what you believe.
In the discussions I’ve had, the question ALWAYS comes down to a person’s epistemology. Two people could observe somebody clinically dead for 3 days rise from the dead and one would say it was a miracle of God and the other would say there’s some as-yet-undiscovered natural explanation for what had happened. We can’t see either. We can’t see God doing it, and we can’t see the undiscovered natural explanation, but both people will believe one or the other based sheerly on faith. Which conclusion is more “reasonable”? I don’t know. What I do know is that if a person’s epistemology is that there CAN NEVER be a supernatural event because there absolutely is NO GOD.... the evidence will ALWAYS end up supporting that in their mind. And the same is true for someone who says there HAS TO be a God. And unless either one has some way for their belief to be proven wrong (falsified), that’s how it’s always gonna be.
We will never be able to convince each other, and that’s fine. Like I said, it’s your life. You want it to be without God and you’ll eventually get what you want, while others will reject God because they blame Him for not forcing you into His Heaven.
I just want those who are seriously pondering their worldview to realize the role that epistemology plays in the FAITH that we all have. Because we ALL have faith in something we can’t see or prove. It’s just a matter of WHAT we have faith in.