

It wasn’t though, was it. The IDF are not Jews in general; they are multi-ethnic and are the armed forces of a country at war. Would a chant of “death to the Russian Armed Forces” be Russophobic? “Death to the Wehrmacht” for anti-German during World War 2? “Death to Hamas” for Islamophobia?
Identification of the armed forces of a state with a state is a sign of fascism, and the identification of the state with an ethnic group is a sign of extreme nationalism - though admittedly that is less the case with Israel and Jewish people.
Chanting “death, death to the IDF” is violent and inappropriate at a music festival. “Fuck the IDF” would’ve been fine though.
I didn’t say anything about political statements, I mentioned violent statements. There is a big difference between wishing death on people and expressing your disapproval with them, and anyone who can’t express the latter without the former should, generally, expect to be censured (and censored). The angry person you quote doesn’t even express violence.