This doesn't really work as a blanket statement. Future proofing and trying to guarantee bug-free code is worth something -- for example if I'm building a space shuttle to go to the moon, I want some degree of certainty that software bugs will not cause that mission to fail, and I might be willing to spend a lot of time and money to ensure that doesn't happen.

I think a more accurate statement of this sentiment is that investing time and effort into preventing future bugs and problems stops being worth it after a certain point (and perhaps earlier than many software engineers would think).