I must admit that I find myself puzzled by acusations that "antisemitism" means "anti-jewish" or "anti-Israel".
"Semitic" is a linguistic term relating to a regional group of languages. Both Hebrew and Arabic are members of this group (as is Maltese). Why is criticism of the horrifying treatment of innocent Palestinian families living in Gaza by the Israeli military termed "antisemitic" when all the people involved are Semites?
You are, of course, correct in a historic context - but anti-semitism has come to mean anti-jewish in more recent times and that seems to be its current accepted definition.
But there is a difference between being anti-semitic (anti-jewish) and being anti Israel, or anti the current Israeli government and its policies. There are plenty of people who are themselves jewish who are strongly against the current policies of the Israeli government. They are most definitely not anti-semitic in my view.
But I do think there is a level of disingenuousness on both sides. Firstly, and most notably, people who throw around accusation of anti-semitism, in an attempt to silence criticism, when an individual is opposed to current Israeli policy. But I also think there are people who are genuinely anti-semitic who hide behind the notion of just being against Israel or just against current Israeli policy when they have a generalised prejudice against jewish people.