One of the most incredible CS things I've ever taken in.
I'm 100% in agreement, this applies not only to languages, but up and down the technology stack. We need to use datastores that support schema evolution, data objects that assume and open world and not a closed world.
Though the lead-in just prior (41:38), is worth hearing, too.
While I was writing a reaction, I thought I should use only words with one syllable, and words defined in his talk.
information; facts learned.
realize; be aware of
Other than the great information he gave, writing this reaction taught me how hard it is to write in this style, let alone talk for a hour. I also realized how much long words I use.
'Writing' and 'syllable' had their senses defined by Guy L. Steele in his talk, as did 'senses' and 'defined' and 'speaker'.
As I now think on this, I note that the post in which you note errors could change 'action' to 'act', change 'let alone' to 'much less', and change 'only words' to 'no words but those'. The definition for 'realize' is in need of a new definition, since 'aware' is not yet a word with a definition.
In truth, trying this mode of speech is bracing, and fun.
Truly, truly amazing.
I don't know enough to take it on though, just thinking of that numerology scene from Pi.