A big reason why this explanation for the existence of everything fails is that its proponents advocate it under the impression that because life on Earth is a thing and the Universe as we know it is so "finely tuned" because there must exist a merciful creator that wants us to exist. The thing that is missing from here is that the Creationists that advocate for this theory fail to understand is that most of the Universe is a death void (black holes and pulsars emitting ionizing radiation, many of the planets that we've found so far (including exoplanets) are uninhabitable, and space is filled with deadly cosmic radiation that you wouldn't be able to survive in without a space suit) and most importantly the people that advocate for Intelligent Design decided to start out with a conclusion (everything exists so therefore God must have done it) and end with a hypothesis (does existence rely on an outside intelligent force) which is not how the Scientific Method works. It's the same classic trap that many Creationists make for themselves that is known as the 'God of the Gaps' fallacy where if you don't know the answer to something, therefore it must be God that did it (imagine having the math question One plus One being presented to you on a test and if you don't know the answer then you decide to choose 'God' as an answer to that math question