RISC-V is atleast 10 years away from competing with x86 and ARM. It is just now getting to a point where it can power arduino class hardware. Long way to go... but looks promising.
I'd bet that within five years a good proportion, even the majority, of Amazon & Google servers, will be running on RISC V chips.
Beating AVR cores on performance is like stealing candy from a baby. No one hands out prizes for that.
Of course that they have better performance... Misleading marketing material.
Can I take the other side of that bet?
I'm mildly bullish on RISC V, but displacing x86/AMD64 in the data center in 2 generations (servers generally have a 2 year refresh cycle) seems fairly optimistic.
ARM hasn't managed it, despite some good attempts. Nor has AMD, nor Power8/9.