Why do people still say "antisemitic" instead of just saying anti-Jewish?

Asking as a former practicing Jew here, no one today really knows or understands the term "semitic." I've never heard anyone called a Semite in my entire adult life. Yet everyone realizes that when you call someone antisemitic, you're saying they hate Jewish people. So why has that term stuck around rather than being replaced with something with a more obvious meaning, like anti-Jewish?