The performance jumps just got more specialized. For instance, introduction of AVX instructions made a huge performance bump for some areas, especially scientific, albeit you needed crazy cooling to run a program using AVX extensively for more than a few seconds. I can remember having around an 80% performance jump with one code I used compiled with vs. without AVX. x86 hardware virtualization extensions were another enormous performance boost. Hardware transactional memory was supposed to be a big (order of magnitude) boost to some things on Haswell but they ended up having to disable it.

Through all this time though, I haven't noticed a massive overall performance boost in a long time. If all I wanted to do was browse the web and read email I'd probably still be using my Core 2 Duo MBP from forever ago. The speed boosts have been piecemeal, one generation improves one thing, the next something else. This is different from Ye Olden Days, I can remember upgrading from a 386 to a Pentium II to a Pentium 4 and each upgrade was so dramatic that it completely redefined what I could do with my computer. The last real performance jump I can remember was the Core Duo upgrade that brought real multicore.

I do kinda miss my beloved old SPARCstation though. Makes me wonder what computing looks like in the alternative dimension where SPARC or one of the other architectures had taken over the PC market like Intel ultimately did.