Personally, I think the 1.3 ROM should be released into the public domain. Both the Kickstart and the source code.
At least then it could go towards some good.
But as others have said, Companies like Amiga Inc./KMOS would never consider such a move, even though the source to 1.3 (it might have been 1.1) was published and publicly available during the commodore years.
A more interesting question is who actually owns the Amiga Kickstart 1.3 IP? If you trawl back through the legal mess that was the Commodore break up and the Escom purchase... you will notice the lack of information regarding the AmigaOS IP... interesting, no?