At the end of the video they say "they envision a growing library online of CMS agnostic front end blocks". They also said they envisage Drupal developers creating custom block libraries as NPM packages.

Both of these statements surprised me & showed some potentially massive innovations in WordPress development that I hadn't expected.

Together these highlighted to me the likelihood of there being many other unexpected innovations coming from the move from PHP based to React based JavaScript WP development via Gutenberg.