Five years? Make that ten; the progress since Sandy Bridge has been incredibly slow. If you take a Sandy Bridge i5 or i7 CPU and turn off the mitigations, it's still within spitting distance of the current i5/i7 models. The only reason I changed out my old i5-2500K two years ago was that the motherboard had finally failed. It was holding up fine with any software I was running, including modern games from that time such as Doom 2016.

Intel really has got to be in an internal panic. The last time AMD pushed Intel this hard, Intel went to extraordinary tactics to push AMD out of the market. I wouldn't be surprised if pushing their workers well beyond safety limits was in the current playbook.