I consider myself an experienced developer and have experienced collegues who likely could not do FizzBuzz or solve simple algorithms like finding duplicates. The worst was when they had high charisma and could talk well in generalites and bluff - took long for management to figure them out.

Experience taught me not to be insulted about those questions. They guarantee all collegues will be able to pass them.

Fizzbuz is not what we're talking about here. It is "balance a tree" with me looking over your shoulder (and $100k in a suitcase) type of problems.

So that if the candidate struggles at fizzbuzz (instead of showing off a well rehearsed set piece), they have an indication that what the candidate told before stems from actual ability and not from ruthless optimization for the local maximum of being good at interviews?