Another anecdote: I'm mostly doing embedded C and I always fail leetcode tests and get my jobs when the interviewers endup valuing more the conversation where I can easily talk about past experience about real world problem I solved or the many time I went to a factory floor debugging embedded system live.

I was working for startup company a few year ago that didn't had yet their leetcode process setup. This startup had an algorithm team working on signal processing and the embed team that pretty much took their python algo and translated them in either C or ASM for some special accelerator + the typical board bringup.

Before using leetcode with new candidate they asked for some volunteer in the team to try it out. I did the test and failed miserably as always. My boss called me to his office and told me, your one of my best guy but you did the worst in the test. I told him this test is probably good for hiring someone for the algo team but for embed it's not relevant at all to the kind of problem we work on.

My boss did some research and found a test targeted at embedded programming. I did the test and got best score in the team (equal with one teammate).

Test are good but you need the right one for the right position. Most of the time for embed job it's the wrong test.