While that's true, I think the OP's point was we knew that emulating the old rigid model was the right thing to do and that the hindsight-is-20/20 lessons we would have had are ones that we instead will need another decade or so to obtain. We lost a lot of time.

The reason for this is understandable and depressing. Frankly most designers were far less flexible than the programmers, and preferred to rest on their own experiences rather than take advantage of the medium.

Frankly the thing that crystalized this for me was the "Cluetrain manifesto". What it said was blindingly obvious to so many of us. What shocked (and enlightened) me is that someone realized that it had to be written down. In other words most people, or at least most people in marketing and business, actually didn't understand the web and preferred to try to treat it as some sort of TV remote control with a buy button.

Of course path dependency is probably the defining factor in technical and social progress. But it doesn't mean there wasn't a missed opportunity. In fact "responsive design" is simply a minor surface metonymic element of a major missed opportunity.