The problem is not with failing to comprehend the complexity of cells though, it's that stuff can't just come to existence given enough time. First of all, the

The problem is not with failing to comprehend the complexity of cells though, it's that stuff can't just come to existence given enough time. First of all, the time is not enough, given the complexity of a single cell, the number of conditions/variables needed for something like that to just blindly happen is absurd, a couple billion years is nothing. Secondly, even if we assume enough time just for the sake of argument, time is not the only factor, you can't just throw "given enough time" and fix everything, things don't just make itself given enough time, a plane would not just come to existence given a billion years. It's very easy to just oversimplify and throw "billions of years" "mass scale evolution", but once you check the details, it's just not that simple.