It’s probably an open and shut case regarding being illegal but prosecution could be hard. How are you going to find the person?

The Israeli police can contact Google, Meta, etc and get the user details.

The question is whether they deem this case important enough, this is a journalist so there is a higher chance but I don't think this specific journalist carry a lot of weight locally

I don't like that the internet can be used to harm you without any recourse.