Question

After I read The Jewish War, I noticed several contradictions between what is told there and the Talmud in Gittin: a) In the Talmud it is told that Nero was not actually an emperor at all, that he converted, and that Rabbi Meir descended from him, whereas there it is told (and in other sources from his time as well) that he was emperor and committed suicide. b) It is told there that Titus did not want to burn the Temple, and throughout the book he is described as a kindhearted person, whereas in the Talmud he is portrayed as the worst of criminals. (Though in this case it could be that Josephus lied, since he was under the Romans and Titus gave him estates afterward.) c) Josephus says that after Vespasian became emperor, he captured Jerusalem and only Titus fought, while Vespasian was in Rome, unlike what is told in the Talmud, that Vespasian besieged it himself (Rabban Yohanan ben Zakkai: “Give me Yavneh and its sages”). d) He also said that Vespasian seized the emperorship by force of arms, whereas in the Talmud it is told that he was appointed after the death of the previous emperor. I would like to know your opinion on the matter, and whether the Sages intentionally changed things, and if so, what the motive was for doing that.