Thanks for the link to Erik's essay - it was a great read.
I like the idea of an image based system, eliminating the need for the filesystem itself. I think the 'filesystem' and 'executable-process' ideas are so prevalent that they frame our thinking, and any new OSes tend to adopt these right away. But more interesting and powerful systems might emerge if we find a new pattern of operation and composition. Are you aware of any image based full stack systems that are in active development?