With browsers the network latency caps the speed ultimately, no matter how fast a CPU you have. Also HDD/SSDs are very slow compared to the CPU caches. Granted PCs of the previous era also had the same limitation but their processors were not fast enough to run a browser 400 times faster if only the HDD wasn't there.
But other simpler programs should be very much faster. That they perceptually aren't is because (IMO) code size and data size has increased almost exponentially while CPU caches and main memory speeds haven't kept up.
Main memory speeds haven't increased like CPU speeds have but it's nowhere close to where it was in 1995. You can get CPUs today with larger cache than I had RAM back then, as well.
I know that CPU speed isn't everything and so a 400x speedup is not reasonable to expect. That's why I hedged and said 50x.
Every part of my computer is a lot faster than it was back then and I can barely tell unless I'm using software originating from that era because they wrote their code to run on constrained hardware which means it's flying right now.
It's like we've all gone from driving 80 MPH in an old beater Datsun to driving 30 MPH in a Porsche and just shrug because this is what driving is like now.
But other simpler programs should be very much faster. That they perceptually aren't is because (IMO) code size and data size has increased almost exponentially while CPU caches and main memory speeds haven't kept up.