...; it would be better for hardware developers if they could run the automated tests on the hardware that they have a vested interest in.
This deserves a few more words because I am contradicting myself: The object of the automated test is to verify the OS (pure software). In this case, the OS is the UUT (Unit Under Test) and the hardware is part of the TTH (Trusted Test Harness).
But that is really only from the perspective of us as OS developers, supporters, maintainers. Someone could take that same automated test framework and verify conformance of custom hardware to NuttX. In that case, every thing is the same, but the hardware is the UUT and the OS is part of the TTH.
Same automated test, just repurposed.