The actual non-obvious test is not a child, but "a person skilled in the art" (of software in this case). You also are talking about the idea, not the inventio

The actual non-obvious test is not a child, but "a person skilled in the art" (of software in this case). You also are talking about the idea, not the invention. The idea was not patented, the technical invention (effectively flow-charts for how to have a button click trigger an auth cookie check, have databases retrieve credit card numbers, etc), which is not obvious to a child. But, I would argue, the details of the invention would be clear enough to someone skilled in the art, another competent programmer.