I follow some of what you said.
you lost me in the licensing argument though, but it sounded convincing :-)
A thought, and I think you alluded to this.
Pegasos makes it known that they allow any OS to run on their hardware and dont request any royalties or such-like for anyone wishing to do so.
So... there is nothing to stop a 3rd party (since we know A1 / Hyperion require a licence before they will let their OS go to other HW), a) acquiring this licence and developing the Pegasos port and b) shipping Pegasos boards with OS4.0
From what I hear pegasos has trouble selling units itself. It'd welcome anyone taking on wholesale lots of its hardware.
The idea could be a double edged sword. This 3rd party could have a pegasos amnesty. Hand in your old pegasos based system and take away a new OS4.0 based system for little more than the 75 USD or whatever OS unit price.
These salvaged boards could then be re-fed through the system, removing MorphOS of course. I dont think you can resell commercial OS's without a licence (in this case MOS) :-)