Why is Ruby more suitable for Rails than Python?
Python has a whole host of Rails-like frameworks. There are so many that a joke goes that during the typical talk at PyCon at least one web framework will see the light.
The argument that Rubys meta programming would make it better suited is IMO incorrect. You don't need metaprogramming for frameworks like this.
So I think we can conclude that Ruby are not better (and likely neither worse) than Python in this respect.
Python and Ruby are usually considered to be close cousins (though with quite different historical baggage) with similar expressiveness and power. But some have argued that the immense success of the Rails framework really has a great deal to do with the language it is built on: Ruby itself. So why would Ruby be more suitable for such a framework than Python?