ganesha is symbolic ,

it is the principle of mastery over obstacles, vighnas,

he is lord of obstacles, vighna raja, vighneshwara,

 has lordship over obstacles,

he can create obstacles ,

he can remove obstacles,

he is vighna karta,

he is vighna harta

to reconcile this and to understand, let us understand how a on / off switch functions in a circuit

 we can understand the role of switch to pass current or to cut off

one to gain mastery over the switch to carry on trials

even a tap / valve on a pipe line is similarly a n example of how the principle of vighnaraja works

 other examples are, traffic signal , vehicle brakes/ speed breakers, dam on a river , etc so the principle of vighnaraja does exist