This is not at all surprising.

[Behind the Aegis]

Americans who are middle-aged or older tend to get their information from legacy media outlets, which, for all their flaws, normally have editorial processes that eschew explicitly racist material. Younger Americans, by contrast, are likely to trust and get their news from lightly moderated social-media platforms, which often advantage the extreme opinions, conspiracy theories, and conflict-stoking content that drive engagement. This bifurcation of information has consequences. Figuring out who was responsible for a national calamity, for instance, takes time and investigation. Blaming that calamity on the Jews does not.

They also do not like when we criticize those who refuse to stand-up to anti-Semitism or do it in a milquetoast manner, along the lines of "all bigotries matter". They try to and often succeed in silencing Jewish voices, even in Jewish spaces, because "Jewish anger" is more offensive to them than actual anti-Semitism.

"A lie will go round the world while truth is pulling its boots on.": (By C.H. Spurgeon, 1859).

This is even more true today when someone can instantly post something to social media and it is taken as gospel. Never mind the proliferation of AI generated fakes and "eye-witness accounts" from people not there, and the ever present 'bots which plague all places on-line.