It's the Dunning-Kröger in action; people like you believe that somehow our universe, reality, the nature of humans, are perfectly definable. What you're not realizing is that the concept of God goes beyond any attempt to rationalize; I don't use rationalize in the context you're thinking, but in the mathematical concept of rationality. Language, how we code information into words, is based upon rational polynomials whose coefficients and values take on the alphabet; binary systems being something you may be familiar with. As soon as you codify 'God' as something rational ('sky wizard?') you imply a limit and impose boundaries on a limitless and indescribable entity.
But if you're trying to just mock people for believing something you don't understand, that's fine too, I've always found the most insecure and least intellectual to be the ones that try to show others how "smart" they are.
That's just mumbo-jumbo of the "not even wrong" category.
If you want to make the claim that there are things in the universe that we can't ever understand and/or are fundamentally non-computable (in some mathematical sense), I can't fundamentally disagree. Nobody knows whether that's true or not.
It's a long stretch from there to any notion of God, though.
There is no mechanism by which the ABSENCE of a belief in your parent's invisible sky wizards becomes just evidence of an alternative belief system.
Not believing in the tooth fairy does not make my understanding and endorsement of say, the periodic table, an equivalent, dogmatic, religious, ineherited-from-parents belief.
The two are not the same. One is better.