As mentioned in the blog post. I wouldn't probably put a "real" production app on it so easily. You can replicate the same effect and more on a service like hetzner. But if you have a Raspberry Pi laying around and like 2-3 hours. At least a blog is enough! And the amount of hardware related things you'll learn is massive.

I've been running a few web bootcamps in the past. Explaining the hardware part through cloud admin panels is extremely hard. Having a physical thing right in front of you is spoko simple. Much easier for people to *click.