still be easier to understand and reason about than the latter because the former was designed to be easy to understand. All those things you mentioned: clean

still be easier to understand and reason about than the latter because the former was designed to be easy to understand. All those things you mentioned: clean separation of concerns, standard libraries, etc, are only easier to understand if you already know about them. If you have no clue what a standard library is, what it does, or how it fits in the design, then you're faced with more complexity to understand than a code which implements everything from scratch.