Vlad,
It's funny then how the non existence of God, being a positive assertion…
...that no-one here makes.
Yet again:
Person A: “God(s)/leprechauns exist, and here are my reasons for believing that”.
Person B: “I have examined your reasons, and found them to be unsound. Therefore I don’t accept your claim about the existence of god(s)/leprechauns”.
Person A is a theist/leprechaunist.
Person B is an a-theist/a-leprechaunist.
Notice here the following:
1. The object of the claim (god(s)/leprechauns) is irrelevant. All that’s relevant is the quality of the arguments attempted to justify the claim.
2. The a-theist/a-leprechaunist does not state the non-existence of god(s)/leprechauns as you wrongly suggest. Either may still exist, but the absence of sound reasons to think they do exist is all a-theism/a-leprechaunism requires.
3. Atheism no more asserts answers to big questions (like the origin of the universe) than a-leprechaunism asserts answers to where the pots of gold are left. All that either depend on is the rebuttal of the justifying arguments theists and leprechaunists attempt to justify their different claims of fact – a simple matter.
Now write this down 100 times or until it finally sinks in.