Have you been able to solve difficult technical problem in the last 5 years, which you can explain in detail? It doesn't matter unless you can code me from scratch a binary tree. Do you have domain experience about something the company work? Cool story, but tell me the proper API call to do this obscure operation.
I understand what's the point of that, I made technical interviews myself and I know is the game to play, but at some point it feel a little weird that you cannot leverage your previous experience and go talk the interesting, actually relevant parts, not the big O of quick sort algorithm...
After playing the game N times (and I don't think I'm particularly bad at it), it gets a little tiresome, I have to say...
It's more about whether or not they are "one of us". I mean, if you couldn't be bothered to brush up on CS fundamentals, how can I trust you with the responsibilities that the job entails? That looks like a red flag to me.
FWIW, when I interview people, I ask actual problems I've run into, i.e. design and implement a sane concurrency system that's easy to reason about on an embedded platform with limited resources.