I think Lemmy has a problem with history in general, since most people on here have degrees/training in STEM. I see a lot of inaccurate “pop history” shared on here, and a lack of understanding of historiography/how historians analyze primary sources.
The rejection of Jesus’s historicity seems to be accepting C S Lewis’s argument - that if he existed, he was a “lunatic, liar, or lord,” instead of realizing that there was nothing unusual about a messianic Jewish troublemaker in Judea during the early Roman Empire.
Except a guy called (roughly translated and modernized) Jesus did exist and was associated with messianic cults and seems to have been crucified. Which wasn’t particularly uncommon, either the name, the messianic cults, or the crucifixions. Basically there’s no reason not to accept a guy that seems to be who Christianity is based on actually existed and probably said and did some of the (non miraculous, obviously) things that were written about him.