I strongly disagree. Good developers have a sort of Big-O intuition at the back of their minds that automatically tells them that the nested for loop they're writing to find a string in an array, and using an array in the first place, might not be the right approach.

Big-O applies to a hell of a lot more than just sorting algorithms, and no language lets you ignore the varying degrees of complexity that come from the choices you make.

Good developers consider Big-O implications all the time, without explicitly thinking about it. They don't ignore it.