OK, if you're discounting Christ, you have to discount about half the historical figures you can name. When it comes to ancient sourcing, mention of someone 30-40 years after their death is considered amazingly close. We have less than 0.00001% of the documents and records of the era, so sourcing of ancient figures is always difficult. There are entire kings, emperors and pharaohs we don't have record of until a century after their rule, yet no one says "oh they didn't exist" because the people who study that know how ancient sourcing works. There are battles that aren't recorded until nearly 200 years after they took place.

Some places aren't mentioned once in any sources we can find, yet seem to have been major ports. The city of Chester in the UK was the biggest roman settlement during their occupation and it had an absolutely huge building at it's center that we honestly are baffled by. Evidence has been found of hugely lavish homes and the river in the city seems to have been the biggest port in the UK. The thing is, no one outside of history buffs knows about Chester and it's position in the Roman Empire and it's very very rarely talked about. Why? Because we have one mention of it in all the sources of the era, and it's thought that mention may actually be referring to Manchester not Chester.

By the logic of "Christ didn't exist", nor did Chester. Christ existed - really that's consider a fact among 99.9% of historians and scholars. That 0.01% is very interesting, but even they acknowledge that their argument has flaws. The idea of Christ not existing is born of ignorance of how historical scholarship works - and you're accusing this poster of ignorance towards science. I don't mean this offensively, I'm just telling you that you're accusing this poster of something you're inadvertently demonstrating yourself.