[FullyFunctional]

Since RISC wasn't coined by IBM (but by Patterson and Ditzel) this is just plain nonsense. RISC was and is a philosophy that's basically about not adding transistors or complexity that doesn't help performance and accepting that we have to move some of that complexity to software instead.

Why wasn't it obvious previously? A few things had to happen: compilers had to evolve to be sophisticated enough, mindsets had to adapt to trusting these tools to do a good enough job (I actually know several who in the 80' still insisted on assembler on the 390), and finally, VLSI had to evolve to the point where you could fit an entire RISC on a die. The last bit was a quantum leap as you couldn't do this with a "CISC" and the penalty for going off-chip was significant (and has only grown).