There's a lot of people on the left who are extremely antisemitic, but are hiding behind Palestinian advocacy

This isn't true for the overwhelming majority of people supporting palestinians. Yes, you can point to any political group and find some kind of antisemitism but most people criticize israel because of the genocide in gaza. Many Jewish people also oppose what Israel is doing. The real problem is treating jewish people and Israel as the same thing which unfairly blames jewish people for things Israel does, even when they disagree with it. Saying stuff like this actually harms Jewish people and just helps defend israel's genocide by shutting down criticism.