Different anachronisms imply different things. Not all anachronisms imply forgery. If Romans is referring to the destruction of the temple then Paul didn't write it. If Josephus refers to events that occurred after he must have died, then I agree he couldn't have written about those events. If the evidence is good I'd accept it. You haven't come close to showing this....
Jason seems to be arguing that since some people think Josephus is a little too forward in his claims about the Canon being settled, this by my standards should make his works spurious, because since I argue Paul shows knowledge of the destruction of the temple in Romans 11 and this is anachronistic, Josephus must similarly be spurious.
Like Jason's argument regarding the use of an assistant I think once again he is making absolutely no sense. Any anachronism means a book is spurious? This is pure nonsense. Look, Jason, this isn't hard. Paul died before the destruction of the temple. If he shows knowledge of it and talks about it like it is an event of the past then he could not have written Romans. Canon selection is a process. It is not necessarily a clear line in the sand. The destruction of a building is. Josephus can misrepresent things. He cannot talk about wars that haven't happened.
Keep in mind that I've answered Jon's claims about Romans 11. He left the discussion without interacting with my last comments on the subject.
He assumes that the table of Romans 11:9 is referring to the temple, even though a table isn't a temple and the Old Testament passage Paul is citing, Psalm 69:22, isn't referring to the temple. And even if we assumed that the temple is in view, why would the temple have to be destroyed already in order for it to be a snare to the Jews who rejected Christ? The book of Hebrews portrays ongoing involvement in the sacrificial system, after Christ's sacrifice, as a stumbling block without assuming that the temple has already been destroyed. To use Romans 11:9 as justification for rejecting Romans as a forgery is absurd. It tells us something about Jon's mindset when he's willing to dismiss the weight of the internal and external evidence in favor of Pauline authorship on such frivolous grounds.
Anybody willing to accept Jon's series of dubious assumptions in order to reject Pauline authorship of Romans should likewise be willing to accept the dubious assumption that Josephus couldn't have written a document in which the Old Testament canon is referred to as undisputed. Just as we could reasonably interpret Josephus' comments in a manner consistent with Josephan authorship, such as by assuming that he was speaking hyperbolically or was being dishonest, the same is true of Paul's comments in Romans 11. All you have to do is interpret the table of Romans 11:9 in light of the Old Testament passage it comes from. Or you can grant Jon's claim that the table is the temple, yet still arrive at a conclusion different from his, as explained above. See the thread linked above for more about the problematic nature of Jon's interpretation.
And how does Jon know that Paul died prior to the destruction of the temple? He isn't getting the timing of Paul's death from a non-Christian source. And he's dismissed the Christian accounts of the apostles' deaths as unreliable in the past. Jon wasn't just presenting an argument as to why Christians should think Romans is a forgery. He was explaining why he thinks it's a forgery. Why does he trust the Christian accounts of the timing of Paul's death?