I see all these reports of people in interviews not even being able to pass fizzbuzz, so I thought, has my brain fried enough that I couldn't even do that? I hate leetcode but whatever, can be fun.

Turns out I'm still fine.

But also turns out, while most people can write fizzbuzz, they don't know how to do it as performant and light as possible. It didn't take much to get in top 0.3% percentile. 

I'm thinking maybe, if you are to do some stupid test like this in the interview, maybe that should be what it's about. Do you know what to look for to reduce CPU and memory overhead? Are you comfortable getting into the weeds with that? I feel that's the bigger issue with programmers right now. If you have basic programmer competency, you can study red-black trees or tries or hash maps for a day or two and work out an implementation. It is learnable. But I find a lot of programmers just don't fundamentally think in performance-oriented ways, and they don't want to, they are actually put off by it or irritated by getting into awkward details of squeezing performance.