Explosive Shot is clunky

Why can't this ability be fired on right click or key binds? If I want to fire at the ground, I have to shift click which feels really bad imo. It's an aoe ability but I have to target enemies directly. That shouldn't be the case. Especially because the ability has interaction with grenades. Why even add the interaction if you have to shift click to fire at your grenades? It's a REALLY REALLY bad design....