https://community.cadence.com/cfs-file/__key/communityserver...
So I agree, it takes 7 years. RISC-V is already in production in many places by now.
It's just a question of opportunity for change.
RISC-V while take on when there's a reason to not use ARM and if it's better than the competition (eg: MIPS).
No licensing fees.
Most companies license ARM cores, not the ISA.
Above those simple cores, we should expect to see more and more RISC-V cores hit the same level of "just drop it in for no licensing, already validated, the pieces like register files are already optimized for the process". BOOM is ~Cortex-A9 perf/gatecount/IPC, which puts it into greater than RPi territory (usable, but not really out crazy). There's still work to be done on the higher end still, albeit, but it's not like you can just go out and licence the highest perf ARM cores anyway (those are Apple's).
ARM has an existential threat, IMO.
Perhaps a good comparison point is LLVM. It too originated as an academic project. Again looking at Wikipedia (https://en.wikipedia.org/wiki/LLVM) it started development in 2000, first release 2003, Lattner hired by Apple to develop it 2005, Clang released by Apple 2007 (so ~7 years from initial LLVM creation to serious production use potentially less depends when Apple were using it internally).