Hmm, "innovation" is a sufficiently vague term that I'm wondering how one can support judgements like "If you think the difference [in innovation] from 1970 to 2013 was even half that of any of those time periods, you're ignorant of history." It's hard for me to think of a way to sensibly quantify innovation in STEM*, let alone the arts.

* For example, which was the bigger innovation, Ure's 1830 thermostat or Bardeen, Shockley & Brattain's 1947 transistor? And how ought I interpret multiple discoveries/inventions like the transistor (which was independently patented at least twice before Bardeen, Shockley & Brattain, but never put into production)?