Your computer may not feel faster than a 20 year old PC, but CPUs have gotten way, way faster.
Compare the AMD Ryzen 7 9800X3D to the AMD A12-9800, you go from 4 cores to 8, and you double the power consumption. But it's not twice as fast. It's 10 times faster. Depending on the exact metric, it could be as little as twice as fast or as much as 1000 times faster, depending on the exact operations.
On top of that memory throughput between DDR4 and DDR6 is about 2.5 times faster as well.
Oh and this isn't 20 years apart, this is 7 years apart. 20 years will see almost an exponentially larger gap even still.
I kind of hoped my point would come across more clearly. Obviously my current computer is faster than one from 20 years ago. But, it doesn't really react more quickly. It just does more: higher resolution video, advanced graphics, etc. The moment we add capability we rush to use it all up. This is not _always_ bad when it comes to computing, but I wouldn't mind if people in general had more restraint.
I suppose that's true superficially, but how many of us utilize 100 percent of our CPU and GPU power.
AI datacenters, absolutely. People? Nah we probably use 10 percent for 90 percent of the time.
But when I need to compile MAME, oh boy is it nice having a fast CPU.
Right -- in the details this is heavily task dependent. If we're talking about word processing, then computing has mostly gotten worse in the past 20 years.
If we're talking about video game graphics it's a bit of a mixed bag.
If we're talking about local LLM models then you need all the power you can get.
Etc, etc.
That is OP's point. The underlying technology has gotten faster but the computer you use feels the same as 20 years ago because the software that utilizes it does a lot more too.