Agreed - my point is that I would be rejected from a job in the morning for an inability to write code that I'd be able to write by that afternoon. They aren't

Agreed - my point is that I would be rejected from a job in the morning for an inability to write code that I'd be able to write by that afternoon. They aren't testing whether you can look it up and do it, they're testing whether you have it all loaded into short term memory, on the spot. Like a lot of people, I'm tired of having to reload it all and essentially retake my data structures exam. A lot of us just don't want to interview anymore. I know that if I need to, I can write a BFS or find all permutations of a set. If the opportunity is good enough, sure, I'll study up and get ready to do this at a whiteboard, but it's boring and unpleasant at this point, and I might not get or want the job, so at this point, I rarely bother. Tech interviews are a big part of why tech companies are experiencing a "shortage" of applicants. They're hardly the only reason, but I'm pretty convinced they are a reason.