And yes, people who know technology will do better.. in a technology interview. I suppose I could ask about gardening but that doesn't help much does it?
I’m not talking about people who know technology generally. I’m talking about people who know different technology. The process you’ve proposed, if implemented at, say, PHP shop, will rule out plenty of great .NET developers since the interviewer won’t have the context.
Knowing how to implement prefix tree or a hash table shows that you've learned solutions, but not that you can write good code in a team environment. Frankly I'd take a worse engineer that worked better in a team over a 10x that ends up silo'ed in 95% of cases.
A good algorithmic interview does not test algorithm trivia. The question should be solvable with only strong structured thinking and fundamentals.
For example, the much-derided “reverse a binary tree” question (I don’t ask it but I think it’s reasonable) doesn’t really require a ton of algorithm trivia. The data structure can be explained in a few minutes and the problem definition can be made super clear and crisp.
https://news.ycombinator.com/item?id=23848039
Maybe the content, despite it being able to be gamed and drilled via Leetcode et al, is sound, but the format in which it is tested may not be.
I also think the skill cap on this sort of question is super low.
(I’d put design questions in a different category though)