This is the old "use the right tool for the job" cop-out. The original post went deeper than that. I would summarize it like this: can modern complex, large-scale web apps be built with the tools we have today, be they Python, Ruby or Javascript? Or do we need an entire new class of tools which have traditionally been used to build large scale systems in the past? It's a multi-faceted question of type systems, toolin…
No. It is a special combination of the shiny insecure magic of Rails, mixed with the happy meal mentality and abilities of most Rails developers.