The funniest part of this I've found is that in the rush to replicate FAANG white board interviews most companies end up with poorly thought out questions, with interviewers who are rushed to prep meaning that the question often contain technical errors and the interviewers can barely solve the problem themselves.
I've been on the other side of this process where the "solution" to a technical case study is flat out wrong, but most of the people training to do the interview didn't realize this to the point where the most skilled candidates would likely (and luckily for them) fail the interview by giving the correct answer!
This means that for many interviews at these wannabe-FAANG companies, if you really know your shit, you often have to proactively guess what the interviewer thinks is the correct answer.
I've been on the other side of this process where the "solution" to a technical case study is flat out wrong, but most of the people training to do the interview didn't realize this to the point where the most skilled candidates would likely (and luckily for them) fail the interview by giving the correct answer!
This means that for many interviews at these wannabe-FAANG companies, if you really know your shit, you often have to proactively guess what the interviewer thinks is the correct answer.