"x86 virtualization is about basically placing another nearly full kernel, full of new bugs, on top of a nasty x86 architecture which barely has correct page protection. Then running your operating system on the other side of this brand new pile of shit.
You are absolutely deluded, if not stupid, if you think that a worldwide collection of software engineers who can't write operating systems or applications without security holes, can then turn around and suddenly write virtualization layers without security holes."
Unless the physicists find some way to breathe new life into Moore's law, I suspect we will gradually move back to the mainframe approach of implementing more and more of the low-level stuff directly in hardware.
Power series is a possible contender, but then you see the glory that is IBM behind it, and you know that no one wants to deal with that on the larger time scale (swap Intel for IBM? Why do this?)
Sparc is all but dead. MIPS is effectively dead. I've heard good things on RISC-V, though the question is, who will want to produce a non-differentiated CPU, when others can do this as well ... that is, you can't really extend RISC-V unless you break the ISA.
Then there are the toolchain issues.
Having experienced the Calxeda failure as a partner, realizing that the ARM marketing claims of low power Intel replacement were complete nonsense[1], I am not all that interested in climbing back on that particular heavily hyped horse.
[1] https://scalability.org/2013/12/the-evolving-market-for-hpc-... search for ARM.