Well, hardware-wise you made equivalent of hello world project so of course it is not hard in absolute terms (not to piss on your parade, it's a very cool project, just to have point of comparison).

Just that hardware equivalent of 200K of lines of code would take far, far more time and resources and with way longer debug cycle, especially when you hit the complexity point where bodging few wires to fix the prototype gets harder and harder.

That's what people mean when they say hardware is hard - if you need to start iterating on a board and not just board's software it gets complex and expensive really quick

But it is far better than it was before - I got my 5 board prototype of similar complexity (also esp32 based) within a week, assembled board, for like $100 (and it was my design mistakes that made it so expensive, like picking screw connectors in places that could totally use far cheaper generic part JLCPCB had in stock, i just didn't know any better), just a decade ago that would probably be order of magnitude more expensive.

So yeah, for those that always wanted to build a hardware project, it's probably best time in the history to do that. Both PCBA and mechanical part got cheap and commoditized enough.