Tacitus on historicity of Jesus - reliable source or not?

[Bacon King]

Tacitus was born twenty years after the crucifixion; he was still living in northern Italy at age seven during the Great Fire of Rome (he mentions the Christians in the context of their community at the time of this fire, describing how Nero was blaming them for it). He didn't live in Rome for another decade or so, and he didn't write the relevant passage until ~117 AD, some 53 years after his descriptions took place. It's also worth mentioning that Book 15 of the Annals, where this description occurs, is generally considered to have still been in a "rough draft" stage; he died before finishing the next volume.

He writes as an old man remembering Rome half a century beforehand, using unknown sources- nothing official, either, or he would have gotten Pontius Pilate's rank right. I'm assuming he just wrote what he could recall that had been told by or about Christian beliefs to him over the years, considering that the remarks in question were basically just an aside, where he briefly describes the group Nero blamed the fire on, and so I think it was less likely that he "fact checked" that part, especially considering he died pretty soon afterwards.

I don't know whether Tacitus was a reliable source or not, or whether you can confirm Jesus was a real person based on this account alone, but I do think there's enough evidence to confirm that a sizable community existed in Rome at the time that did believe Jesus was real, yes.