Simplicity isn't always accurate.
Computers are designed with specific purposes in mind, and are efficiently designed to do so. Ideally, redundancies and useless stuff is ironed out in order to create as efficient an experience as possible. The best ones, which includes the ones made by Samsung and Apple among others, also have as few points of failure as possible, with fixes being relatively easy.
However, things that develop via natural selection, such as living things, are often filled with hundreds of fail-points and redundant elements. That is, stuff in our bodies that literally don't do anything, but are hold-overs from deeply distant early human and non-human ancestors. From a design perspective, the human body is actually quite poor; we're incredibly weak physically and continue to get physically weaker through the millennia as physical strength is not necessary to pass on our genes. There are hundreds of ways the human body can fail, i.e., either die or just stop working in such a way as to become crippled.
Speaking as someone who's an amateur programmer and game designer, if there's some sort of intelligent designer of the universe, he or she's a pretty bad designer.