Seems really harsh at 15. I don't know if he intended to do a nazi salute or not, but even it he did, it looks like his career is going to be wrecked for it, which is too much. I did way too many dumb things after 15. He is just a year older than my eldest, and even though she is pretty bright and sometimes considerate, I could see her and her mates doing this for "jokes".
FWIW I used to draw nazi stuff on bags and on paper well into secondary school. It was just in the war books I read, films I watched and a few punk rock bands used it. I don't think I ever thought how offensive it was at the time, and was never a nazi.
Seems younger than Prince Harry with his nazi uniform photo, and we didn't cancel him until he dated a black girl and became all woke