the thing is that the hardware in question _is_ open, you can put whatever you want on it.
however, the FSF doesn't want to say that the hardware is open if the vendor offers closed software on it.
I would love it if all the hardware that has closed software pre-installed on it was also open and I could put my software on it instead.
saying that hardware isn't open enough if it is offered with the option of closed software means that you drive manufacturers into an either-or situation. they can either support the closed software that most of their customers want, or they can have 'open hardware' (even though the hardware doesn't change). there is no company out there that will willingly eliminate all sales for people who want to use closed software to support the people who want nothing but free software.