As someone who's job it is to work on things like this, there's a few things that must be pointed out.
- SPDY runs over SSL. There isn't an unencrypted version -- note that SPDY was in fact faster than HTTPS.
- Many of the tricks used today to speed up page delivery, such as domain sharding, actually hurt SPDY's performance. SPDY's main benefit is that it opens up a single TCP connection and channelizes requests for assets inside that connection. Forcing the browser to establish a lot of TCP connections defeats this entirely, and the overhead of spinning up an SSL connection is very high. (And again, it should be noted that SPDY *WAS* faster, even if just a little bit, than standard HTTPS.)
There are other features in SPDY that today remain largely untapped, such as a server hinting to a client that it knows it'll need some content ahead of time -- giving the client something to do while it'd normally be idle waiting for the server to respond while it's generating the HTML it requested. (Large DB query, or whatever.)
Web engineers are clever and a smart bunch. While it looks like there's not a lot of gain to rethinking HTTP 1.1 today, given the years of organic growth we've had and time spent optimizing an older protocol, as new technology comes along that take advantage of the new foundation, things this will change. Give it time.
To the folks complaining that this guy doesn't know what he's doing, uh, he's a Chief Product Architect at Akamai. Yes he does. The folks at Akamai know more about web delivery than just about anyone.