You could make the same argument for software. Where do you draw the line "starting from scratch" in software? Does incorporating third party libraries make it not from scratch? What about the standard library of your language of choice? What about using the abstraction of a high level language in general vs a low level language, or straight machine code? For that matter, is it from scratch if you didn't design the logic gates on the chip itself? Or perhaps even come up with the concept of logic gates from electrical and material science principals.. etc..
I'd say that if you are gluing together a bunch of known-good components into a specific configuration that isn't a full copy of something else, you're building from scratch.
I'd say that if you are gluing together a bunch of known-good components into a specific configuration that isn't a full copy of something else, you're building from scratch.