I think what jblow is trying to get across is that simply writing an article saying "server side JS and client side packet sending libraries exist" hardly begins to solve the problem of how to implement responsive and robust netcode. Node.js and socket.io are literally technology in the broad sense and make a huge number of things possible, but they offer no help with the hard parts of writing a Real Time Multiplayer game. It isn't relevant, it doesn't facilitate the job, it's the wrong layer of abstraction; at the level of actually making sure your real time game performs well, it is not technology. If the article pointed to an actual netcode library for JavaScript games, then yes, that would be technology.

e: reading jblow's other comments makes me realize he's not talking about this at all. So treat the above as my personal issue with the article.