Conception of good & evil is based on the eye of the beholder. Your definition as to whether it exists, declaratively (upon the evidence you deem necessary), is philosophically equivalent to that which you deride.
The force for good leads to outcomes, same for evil. These outcomes we hope to shape. However you see fit to conceive of these two forces at work is up to each. Existence of this war & it’s correlated outcomes in itself deems both conceptions useful. IOW, evil shills can get fucked. Otherwise same team & to each his own. Preservation of that is WWG1WGA.