This just compares a decent programmer with a terrible one. Not a modern app developer with an old timer. This is especially evident where the systems programme

This just compares a decent programmer with a terrible one. Not a modern app developer with an old timer. This is especially evident where the systems programmer is aware enough to use Go (which is a debatable choice, but certainly displays good awareness), but the modern app dev doesn't know when (not) to use Big Data and when to try optimizing things (e.g. the JSON choice). The only "mistake" I see a modern app developer making might be using Python, but hey, computers are fast (so python should still be fine). Most would probably come up with a similar bit-twiddly solution or a simple DB-based solution. No biggie. There's no dearth of horrible systems code out there either. It might be less likely for a systems programmer (even a horrible one) to mess up this exercise, but you could probably choose an exercise which would have the reverse effect. In the end, it's a toy exercise, not one where you actually design a significant piece of software. There is a point buried in all of this; which is that learning systems programming will probably make you a better modern app developer since you get the correct mindset to tackle problems like this (also, vice versa?). But there's too much hyperbole obscuring it. There's also the other point about how systems programming is done vs modern app dev. It's a valid one, but there are benefits to both approaches, and it boils down to each being useful in its own domain.