WebSockets are a tool like any other and as usual, picking the wrong tool for the job is a great way to shoot yourself in the foot. Agree with the author that they aren't suited to replace HTTP but I don't see the need for this apocalyptic tone. WebSockets have been available in many tech stacks for a while now and we don't see much abuse. Developers disciplined enough to stick to Rails don't seem overly prone to jump on the new shiny toy without thinking.

Web Sockets are great to bring some of the more heavy duty apps from Desktop/TCP to the web. PubNub, Pusher and the likes show it is possible to achieve reasonable scale.