I worked at a Java shop for a while, with a small and new-ish codebase built by experienced devs, and most of the errors we encountered were null pointer exceptions. It was always just, "alright where do we need to add another if-statement this time"

Of course you could be "defensive" by adding an if-statement every single time you use any object. But that would mean an order of magnitude more lines of code, and even then it would be easy to miss cases