Smaller animals are aggressive toward larger animals all of the time Sparky. Clearly the possum wouldn’t leave or else they couldn’t have been hitting it with a shovel. There is no reason for you to be projecting that this man is a liar.
Possums are no better than rats and killing them is a perfectly sane thing to do.
As to you dealing with possums all your life do you mean you raise them or breed them for possum shows?
If possums are causing normal people problems they kill them.
Oh what a bunch of bullcrap, Skippy! You are so misguided on so much. You harbor the typical ignorance of so many. Someone taught that you do such things to possums, and you were never able to learn your way out of such nonsense. So be it. Defend yourself against such aggressive animals! They might attack at any moment!