This. A decade ago, during my summer internship in the first year of college, I got put on a hardware project, basically designing a remote monitoring device for a telco.

I wrote the software, and my friend designed the PCB for the digital side. Basically I had to be a decent C programmer, and read the datasheet for the MCU we were using (which was way more work than using something like an ESP, but still). My friend had to lay stuff out on the PCB and place secondary components according to various application notes.

Overall not simple, but not rocket science.

On the other hand, the guys doing the analog daughterboard were industry veterans with decades of experience. They had a million concerns, from signal integrity, to voltage protection, back-EMF, etc. I was not even near the ballpark of that skill level.

Later on, I worked on more complex HW projects, stuff with FPGAs, DRAM integration and 8 layer PCBs, where you had to run full electromagnetic simulations because when you run at 1+ GHz, suddenly signal propagation is not instant, and traces behave like antennas.

I also did software there (a smaller slice of it this time), but there was an army of engineers working on the whole project which took a year, and not a second of it was spent in vain.

I agree with everything you're saying, but if you consider that this is a single-person company, the "hardware is as hard as you make it" statement makes sense. He saw a need, found out that it would be feasible to make a product to fill that need with very simple hardware, and chose to make the product. If solving the problem would've required hardware outside beyond their budget or skill level to make then presumably they wouldn't have pursued the whole project. Which I guess is sort of the point, but of course the title of the blog post doesn't really convey that.