Biology, and by extension medicine, only started to look like engineering in the last ~50 years because it requires serious advancements from many other fields of science. As in, you can't discover cells if you haven't invented a microscope yet. It's literally reverse engineering alien technology, in the sense that it's something that wasn't created by humans. And you can't really reverse engineer something when you don't have any tools to meaningfully interact with it and pick it apart.