I've interviewed tons of engineers that ace the interview and you have no choice but to pass but you see later on writing abysmal code. The problem is that design, quality, and maintainability are not valued. As a result, you end up with extremely mediocre "hacky" engineers at larger companies that can spit out tons of valid code but lead to a tangled mess shortly thereafter.

Worse, there's this huge emphasis on "big O" with zero focus on clearly egregious bad practices (tons of copies, outrageous memory usage, casting between strings and numbers all the time). I've rarely seen clearly bad algorithms be deployed but I have seen plenty of unperformant code go out.