That anyone reasonably clever which spends months studying CTCI, EPI and Pramp and whatever else and doing mock interviews will pass the interview, while an experienced programmer will not just by virtue of their skills and knowledge.
Spoken like someone who has never interviewed at Google.
I have 6 years experience, a M.S. in CS, have worked at SV unicorns, and studied for 2 months for my Google interview and still failed. Am I an idiot? Possibly, but more likely that the interviews are hard and there is a lot of randomness.
Until you actually study and try yourself, don't talk about how easy it is for anyone "reasonably clever".
I have performed a lot of coding interviews (probably 400+), I'm painfully aware of how limited the signal is that I can reliably read from 45 minutes with a candidate
I deliberately ask a question that has no algorithmic or data structure component to it (and tell candidates that) it's just a simple problem solving coding question which allows some insight into general coding and engineering chops
I still see experienced engineers struggle. It is hard to pinpoint exactly why, but lack of preparation/practice definitely seems to be a problem
Covid appears (at least for me) to have killed off the whiteboard
I've seen experienced engineers who I know for a fact can code and solve problems decently completely freeze and blank out during easy live coding challenges.
I think interviewing is a stressful situation. It's hard for reasons outside an applicant's knowledge or intelligence. Interviewing seems to be a skill in itself. I know I hate it... :(
I don't know if that's still a problem at Google, but it could explain why some people don't pass the interview process even though they are reasonably clever.