You seem to be making over Professional Historians in your own image here. I'm sure there are professional historians of all stripes of informed opinion.
I will however put your claims to the professional historians of my Ken to check if professional history is avowedly, publicly, professing, messaging board contributingly, atheist.
You keep tilting at windmills for no apparent reason, Don Quixote.
The provenance problems with the NT have nothing to do with atheism: they involve the absence of details about who wrote what, when (they weren't contemporaneous) and where they wrote it, whether they were biased or had a vested interest of some sort, the risks of mistakes of lies being introduced, the problems of translation, that the original documents aren't available and that the earliest documents now available may have been post hoc edited or amended (since there are no originals to compare with).
Even an everyday Christian, or a theologian, should be able to appreciate that these provenance matters are relevant. Presumably, their attachment to the NT is driven by their faith rather than seeing the content as documentary history, especially given some of the fantastical claims being made in the NT.