As I see it, these systems have two potential markets (some natural overlap exists): the first being people like me who don't want to necessarily feed the x86-6

As I see it, these systems have two potential markets (some natural overlap exists): the first being people like me who don't want to necessarily feed the x86-64 beast if they can avoid it, and the second indeed being people who want a completely auditable, transparent platform. In both cases to be a practical alternative the computer needs to have similar performance to what you'd get from a modern desktop, and while POWER9 is no longer cutting edge, it still generally delivers.