I’ve been working on a hobby project for about 6 years, and early on I got very excited about productizing it. It led me down some interesting paths and really made me think about overall BOM cost, designing for assembly, ease of use, etc. It also revealed some weaknesses for me, as I kept making decisions based on something I was sure I could figure out, rather than what I actually knew how to do.
Eventually I switched some things up and it got much easier.
I'd read this article!
There is if you don't have the expertise. Of course, arguably if that's the case, you shouldn't be developing such a product anyway. But as the post detailed, by switching to a Pi Zero and removing the Adafruit HAT, the BOM costs would already drop significantly. I think if you're smart about it, you absolutely can build a viable product this way. Certainly not as profitable, but possible.