“My theory is a lot simpler and can never be disproven - God created the universe.”
The Big Bang Theory is essentially that. It is a theory accepted by scientists that the universe was created from nothing by something.
Science can’t say what that something was, but God is the only explanation that fits.
“Science can’t say what that something was, but God is the only explanation that fits.”
“God did it” is not an explanation. Nor does it invite scientific enquiry.