I think this is following "A creation proves a creator." line of reasoning, which the OP title doesn't really seem to properly indicate. Having said that, I will give this guy credit for one thing.
Whether this YHVH-Yahweh is a personal God, whether he answers prayer and does miracles and is in fact a Trinity of Three Persons united in one Godhead and whether the second person of the Trinity became incarnate of the Virgin Mary and died on the cross to redeem the human race–all that is another matter entirely.
If we humor the idea that his above reasoning is correct and that there is a god, then this is a good point. That is, arguing for the existence of a god is different than arguing that said god is how you imagine.