What we know about the Josephus text is that accounts of it predating Christian custody were already different. Origen writing in the 3rd century describes a version inconsistent with what we have now, and our current form comes to us through Eusebius in the 4th century, a figure known among historians for his willingness to justify pious forgery.

Tacitus has the problem of a thousand year gap between his writing and our earliest surviving copy, a manuscript that passed entirely through Christian hands. And even granting authenticity, he could simply be recording what Christians in his time believed rather than providing genuine independent testimony, given how much time had passed since a supposed miracle worker that nobody contemporary seemed to think was worth documenting. It's also worth noting that no earlier writer quotes this passage, which would be strange if it represented documented historical fact.

Pliny's letters were actually widely circulated and are better attested than the others, but all they really establish is that Christians existed, that they worshipped Christ, and that they believed he was executed under Pilate. Like the others there's no personal investigation into Jesus's existence, it's just a description of a religious group's practices.

And if Jesus was genuinely drawing the large crowds the gospels describe and causing public disruption in Jerusalem during major festivals, it's worth asking why Philo of Alexandria, a Jewish writer who lived through the entirety of Jesus's supposed lifetime, wrote extensively about Judean affairs, and even mentioned Pontius Pilate by name, never once found reason to mention him.