Just because they are not native doesn't mean they can't live there, but they shouldn't live while oppressing the native Palestinians and prevent them from returning in order to preserve an ethnic majority.

Jews outside of Palestine are not uniquely descended from Jews that lived there 2000 years ago. Also the idea of Jews as a homogeneous people is a fairly recent phenomenon, people married into Jewish families, converted etc...

Even having mixed parentage can make you an oppressor. During slavery, mixed race people were often used in Brazil to hunt escaped slaves. At the end of the day its not about people's parentage but to what group they get put into and whether they choose to use any privilege they have to fight against oppression.