Almost all modern scholars reject the authenticity of this passage in its present form, while the majority of scholars nevertheless hold that it contains an authentic nucleus referencing the execution of Jesus by Pilate, which was then subject to Christian alteration. See https://en.wikipedia.org/wiki/Josephus_on_Jesus#The_Testimonium_Flavianum

The real passage was probably more like this.

About this time there lived Jesus, a wise man. He won over many Jews and many of the Greeks. When Pilate, upon hearing him accused by men of the highest standing among us, had condemned him to be crucified, those who had in the first place come to love him did not give up their affection for him. And the tribe of Christians, so called after him, has still to this day not disappeared.