Now support calls on a web app are unlikely to be related to the technology used on the server side. Usually they are more related to the design of the application itself or what resides on the client side.

It also depends on the number of users, if they only have that little number of rails app, its probably because started using to test the water, and I doubt they used the large applications with a ton of users to begin with. If you have less users, you have less support calls. Applications that are critical or have to adapt to unplanned conditions also get more support calls. I could come up with similar figures for Lotus Notes, Oracle forms or excel spreadsheets based apps.

In other words, the article doesn't really mean anything.