How certain are we as to what Jewish people looked like at that time? As far as I know, he could well have been blonde with blue eyes. The Shroud of Turin suggests a strong Viking-like look (to me!).
Note on red hair:
Facial reconstruction exists for that era. They weren't 6 ft and pale.
Of course we can’t know for certain. But Roman burial paintings of the period show what Mediterranean people typically looked like and it’s pretty much the same as they are today. I just find this quasi-Nordic buff blonde Jesus with the Hollywood beard stubble a little bit jarring.