I’d add another factor to #1: this feels objective and unbiased. That’s at least partially true compared with other approaches like the nebulous “culture fit” but that impression is at least in part a blind spot because the people working there are almost certainly the type of people who do well with that style and it can be hard to recognize that other people are uncomfortable with something you find natural.
I would say that it makes the interview process more consistent and documented, and less subject to individual bias. However there's definitely going to be some bias at the institutional level considering that some people are just not good at certain types of interview questions. Algorithm and data structures questions favor people who recently graduated or are good at studying. Behavioral interviews favor people who are good at telling stories. Etc.
Yes, to be clear I’m not saying it’s terrible - only that it’s not as objective as people who like it tend to think. In addition to the bias you mentioned, the big skew is that it selects for people who do well on that kind of question in an unusual environment under stress, which is rarely representative of the actual job. That’s survivable for Google – although their lost decade suggests they shouldn’t be happy with it – but it can be really bad for smaller companies without their inertia.
