Question

Why is it irrational and unproductive to try to "prove" or "disprove" the
existence of God?

Answer 1

It's not worth it.

Step-by-step explanation:

I'm a believer, but if people are really sure to believe that they were created by the big bang, or by a superior creature they will believe it no matter what evidence you provide. Another example of this is flat-earth believers.

It would just be a waste of time, depending on your audience of course.