Hi Stuart! I'm an engineer at Suitable Technologies (makers of the Beam). Sorry to see the Beam didn't make it into the video, but it was really inspiring to see this talk. Thanks!
It's hard to get conference venues to care. It might require an interpretation of the Americans with Disabilities Act (in the US) to insist that reliable WiFi to support remote video attendees is as important as reliable elevators.
However, is a really interesting point about the reliable Wi-Fi in public spaces. If telepresence is going to be used as a viable way for quadriplegics like me to visit these public spaces, then we're going to need decent and dedicated Wi-Fi. Which in 2014 is both fairly easy to do, and not that expensive. But you're right, I do fear that it may need some Interpretation of legislation to make this work. In the UK we have to Disability Discrimination Act [0] which I think of is the same things as the ADA in the US.
[0]:http://www.nidirect.gov.uk/the-disability-discrimination-act...
however often a problem with conferences and large gatherings is that even if there are separate Wifis and on different channels the (constructive/destructive) interference is still bad enough that the connection slows down anyways.
I know there are solutions out there, it's a matter of cost and time before they become widely available. (I'm hoping it will happen tomorrow ;))