It was written when Moore's Law was in full effect. You cannot continue to expect the hardware to catch up - and certainly not in a nice predictable curve requiring no rethought of your software paradigms.
The pace at which more transistors are squeezed into the same amount of silicon has slowed down a bit, but the real difference between today and 20 years ago is that we've crossed the "good enough" threshold, and now we are optimizing other dimensions, like cost and portability. A good computer for web browsing and reading mail in 2006 is still a good computer for those tasks today. Back in the 90's, a videogame company that didn't release a new console generation after 3 or 4 years was dead; how long has it been since the Xbox360 and the PS3 were released? And nobody is clamoring for more polygons, so instead Sony is releasing a new PSP with roughly the same power as the PS3.