what does the "designer" look like?
"There must be something" isnt a compelling argument
Who knows. Maybe it is not visible. There is "nothing behind it all" is also not a compelling argument. Until atheists can describe why anything in the Universe exist as it is they don't have an argument at all. How can atheists be confident there is no Creator when they can't even explain why atoms exist?
Atheist take a lot of things for granted that just exist. Why is there gravity? And responding because mass creates gravity is not an answer. Why does mass create gravity? Maybe it could have been the opposite? Mass could have pushed away instead of attract.
The next favorite response from atheists is yes, that could be possible in a multiverse where there are infinite universes. Well, that's an even more farfetched and complicated concept than the more simplistic model of a sentient being or power was responsible for it all. And a multiverse theory still cannot escape the argument that a Creator or Force could be responsible for it all.
It is a wild concept to try and understand for sure. Why is there anything, and not nothing. What created the Creator?! What created the entity that created the Creator? Etc. Are we in a simulation? Note that a simulation still alludes to a Creator that runs the simulation.
It is hard to wrap our human brains around this kind of shit. Maybe AI will eventually figure this shit out once it matures to real intelligence.