I recently watched a video of a hiring manager at a FAANG company that says he asks algorithm questions "to avoid false positives." He says he doesn't ask about the day-to-day job because that somehow is more misleading. IME the vast majority of any senior engineering role is to be able to dig through spaghetti and figure out what's going on. What's more likely to give you a false positive on if they can do that--asking them a question you can only solve if you know the implementation of a knapsack algorithm off pat (in a job where that has never been needed in the history of ever) or handing someone a plate of spaghetti and seeing what they do with it (or at least asking them how they approach spaghetti when they encounter it).