I'm thinking this must be an age thing. 15 years ago isn't a significant portion of my lifetime, so perhaps I see the progress in that time period as not being tremendous. Perhaps you're younger. I've been active in this business/space/industry since around 1975 and for me not a whole lot has changed. Sure today you can put a thing with the power of a VAX on your wrist, but we expected that to happen back in 1980. I moved into the house I live in now 15 years ago and immediately set out to build myself an internet connection. I used 802.11b products that are not too different to what we use today.
The one thing that has changed in the past 15 years that I see clearly is there is much more data available on the Internet, but that's just a simple adoption curve effect. Back in 1992 we had the Microsoft Developer Network on CD with a search application that ran on Windows. It was basically the same thing as Stack Overflow, except of course much slower to update and featuring contributions from vastly fewer people. But essentially the same thing. I even remember having discussions in 1992 with colleagues about how the MSDN would surely evolve to be Internet-based rather than delivered by mail on a CD.
