I agree that big companies have interviews that look more checkboxy since they generally want interviews to be standardized/fair for candidates, but even then,

I agree that big companies have interviews that look more checkboxy since they generally want interviews to be standardized/fair for candidates, but even then, a lot of the interview is not about the solution to the problem per se. For example, if the candidate struggles with basic syntax, or if they struggle with refactoring, or they don't react to feedback well, these are all things that get considered, even if they do solve the question optimally on paper. I had one where we solved the problem half way through the session and went on a big tangent about how to engineer a solution to a related fuzzy problem. I do agree though that interview standardization can lead to mediocre interviewer practices if the interviewer isn't truly committed to improving their recruiting skills (which is sometimes the case if a team is on a crunch, for example).