The person I responded to showed that the financial goal is hard to reach. Like I said the point isn't too cause financial harm per se, just to show and expose the moral deficit of the state.
The voor is that such a boycott will result, or the Israeli state changing is course (however unlikely).
The bottom line is it's not too cause any harm at all, be it financial or physical, it's about stopping the war and the way Palestinians are treated by the Israeli state.