@mangeurdenuage @idiot @Zergling_man @lanodan @sun You also need a lot of money especially if you want your hardware to be affordable, and much, much better governance than the FSF for example.
For profit companies have an implicit advantage there, if they completely screw up they stop making money. Whereas Gnu Hurd is still on its road to nowhere thirty four years after it formally started.
But with money also comes temptation, see the Raspberry Pi for example (switched over to prioritizing companies that embed their stuff, is now doing an IPO).
I can't think of any high volume open hardware projects that either avoided that fate (of course Raspberry Pi actually wasn't very open, but that's in part on Broadcom etc. and the latter's making too many of a certain chip) or got anywhere, see for example lowRISC which was founded to make a very interesting RISC-V chip, as in they talked about what it would cost to make N-thousand working ones, and ended up being a consulting company.
See also how much it costs up front to make good injection molded plastic parts for packaging, that's generally needed for high volume parts for consumers. Every time you see something that's metal, CNC machined, and/or 3D printed you know it's going to be extra expensive.