Here is what I do, the robot shoots arrowIcon when fire1 pressed, and the robot have different tag with the arrowIcon, for the Crate Object, I created a FSM that listening for collision on the first state (first state does not contain any action at all), with Transition Collision enter 2D, when any object collides with the crate, it will automatically activate that transition.
On the second state, the first action will store the game Object that hits the crate, and we will check if that game object have certain tag that we're testing, if its true, then go to destroy, else it will go to Don't destroy transition. I've tested it, and it works, the crate only can be destroyed if its collides with arrowIcon, if I try to move the robot to collide the crate, it will not be destroyed.
hope this helps (I've attached the FSM for the crate)