I don't believe he has the required evidence to make this claim.
(1) I have a lot of non-techie friends that are interested in using this just to try it out -- they are early adopters but consumers instead of creators; they do not have technical ability.
(2) Whether or not Plus gains market traction is dependent on how it fits into the current social application space. 'Hangouts' and 'Circles' will help differentiate them but to gain a foothold the network effect is of greater importance. Google are making a very calculated move by inviting people with higher quality social graphs as this will help them here!
Plus' success will depend on:
(a) whether they can keep non-techie early-adopters interested in the new features they are providing.
(b) how well they manage to cross-pollinate between each of the services in their eco-system: the changes in Gmail, the navigation bar, and UI across their services point towards them realising this.
(c) easing the move in-between other social applications by providing APIs that could be accessed by more generic desktop and mobile applications that users often use to interact with networks: Tweetdeck, etc... As I said, it's all about harnessing network effects and getting the right people on the service. At this point, I don't see any reason to doubt they have momentum and if they're smart they will continue to connect their eco-system together in a way that creates long-term growth long after the buzz dies.
(3) It's quite presumptuous to assume that since many early-adopters are techies that this is how it will remain: does anybody remember when Twitter was only used by techies?
Let's just see how it plays out and avoid creating mindless tech gossip...?