It helps to understand Zionism as pushing for effectively an ethnostate or a state run by/for a specific population of people as defined by a specific, mostly non-transferable trait.

Stepping away completely from Israel or Zionism, any state that is specifically for a certain group of people is a state that is going to be explicitly not for any other group of people.

If you wanted to start a country that was run entirely by and for people with natural brown hair, anyone living in the area where that country was created who didn't have brown hair would be a de facto second class citizen and the state would have to take explicit measures to exclude those people and limit their ability to participate in the running of that state. You have at that point the bones of an authoritarian state because the focus is on the control and exclusion of certain groups.

This is absolutely unavoidable. Any state founded on the idea of exclusivity has to maintain that exclusivity somehow.

Going back to Israel, it's definitely a valid point that, historically, Jews have faced a wide range of problems being a minority in different places and especially because of the Holocaust it's a credible fear that the Jewish community has of being targeted again in the future. That said, does that greenlight the creation of an ethnostate? I would say no.

Antisemitism is still a problem, sure, but I think it's a pretty difficult case to make to say that places like the US are, on the whole, dangerous for Jews.