To take HN's fave example Rust: it has a type system that removes "viligance and dicipline" as a requirement for memory management. We don't need as much care if we can codify checks and standards that make bad practices (null pointers etc) impossible.
I work mostly in Python, and even using neat tools like Vulture, dead code elimination is a mostly manual, care-requiring task. I wonder if there's a neat way to bring down excess code- I don't have any new ideas though.