Historical evidence is evidence plain and simple.
Historiography never was as objective as you make it out to be. If you don't believe me just look for the discussion of Tacitus' "Germania" and what the author might or might not have intended. Also he is almost 80 years too late to record anything but hearsay on the matter of Jesus.
Interesting is which historiographers and ethnographers FAIL to mention Jesus. Neither Philo of Alexandria nor Justus of Tiberias mention him.