This is the argument I should have used in the post, having slept now and my thoughts being more clear:
There are really three, separate things under consideration here:
- What is the expressive power of the language's syntax?
- How strong is its standard library?
- How strong is library coverage for common tasks?
The first question is what the second example tries to demonstrate, i.e. "How concise could this be made in Ruby?" The second question, I agree with you mostly. There are outliers like C++ with an especially poor standard library, but in general, that doesn't speak to the language's innate power. And in the third, I hit at in the post by saying that I feel this particular task is a bit contrived with respect to Arc: it shows simplicity in things that I wouldn't necessarily look for in a web programming language, but lacks things that I would expect (i.e. the ability to connect easily to web services APIs).