There is an absolutely fascinating new NBER paper out (“Five Facts You Need to Know About Technology Diffusion”) on technology and innovation. Most of you will not be able to pull up the full paper, so you’ll miss the discussion about some markts where S-curve adoption models don’t work, but here is one factoid:
The speed of convergence for technologies developed since 1925 has been
three times higher than the speed of convergence for technologies
developed before 1925.