You realize most of those attendee's are major companies right? While in the past a lot of "consumers" would manage to get a ticket to this, these days its massively frowned upon and I would venture to say 80-90% of those tickets went to companies looking to send their developers for facetime with the heads of Apples Mac and iOS development teams about issues/concerns/ideas.
The days of jackasses like Violet Blue coming to a developer conference to hob nob when she doesnt know shit about being a developer have long passed when people started to care about app development and iOS.
The interesting thing about this question is that it is quite clear from the several early papers that it was an ancillary point for the Dynabook to be able to simulate all existing media in an editable/authorable form in a highly portable networked (including wireless) form. The main point was for it to be able to qualitatively extend the notions of “reading, writing, sharing, publishing, etc. of ideas” literacy to include the “computer reading, writing, sharing, publishing of ideas” that is the computer’s special province.
This has been absolutely done by the iPad and other tablets. People love to make the claim you can not create content on the iPad but its been proven time and again for the most part to be false beyond a few exceptions you can create just fine. People code on them, people write blogs or even books on them, people record and perform music on them etc. They are still a Gen 2 device atm though regardless of the marketing speek (or maybe Gen 3).
Isn’t it crystal clear that this last and most important service is quite lacking in today’s computing for the general public? Apple with the iPad and iPhone goes even further and does not allow children to download an Etoy made by another child somewhere in the world. This could not be farther from the original intentions of the entire ARPA-IPTO/PARC community in the ’60s and ’70s.
Even this is disingenuous because Apple doesn't in any way prevent a people from creating a good app uploading it to the store for free and let people download it for free. It shows a blatent misunderstanding of the app store, and reasons behind it. It also shows a 60/70's naïvety toward how nasty our computing world has become toward attacking other users for personal and political gain.
I have a theory that it's impossible to prove anything, but I can't prove it.