As a former interviewer at Meta who did hundreds of technical interviews, I can tell you that the people that I hardly expected "Djikstra or Knuth". Honestly I gave pretty reasonable questions that were similar to the types of things I would do in my work (with some modifications to work as an interview question). And still the majority of people didn't do great. It's even worse at the "screen" stage, where I've had people that, e.g. didn't know what "function" means or couldn't write a loop to find the max number in an array.