The question that shatters faith, forever.

[Minimalist]

The OP suggests that without historical support Christianity falls apart.

There is a bit more to it than that. To quote H. L. Mencken:

Either Jesus rose from the dead or he didn't. If he did, then Christianity becomes plausible; if he did not, then it is sheer nonsense.

So, at step one we need some historical reference to an actual person and then they need some evidence that he came back from the dead...and rose to heaven and all that stuff. They have actual evidence for neither but it is not too much to ask that they demonstrate that there was such a person to then meet condition #2.

Again, these are burdens that we did not hand them. They are stuck with them because of their own beliefs.