I wouldn't say any approach is better or worse, it has to fit your personal style. I like the Ruby approach, others love the Python approach. This means that Ruby breeds a lot of interesting stuff, but with less stability guarantees.
At the same time, Rails still builds on the ideas of Rails 1, which is an achievement in itself. So Rubyists is not totally not caring about backwards compatibility - they just tend to throw out bad ideas quickly again.
On the other hand, the quick pace allows the MRI team to build improved interpreters with a reasonable chance of quick adoption.
This is a much more fundamental difference than any snickering about the garbage collector of the main interpreter, from a users perspective.