The "rubyist" is completely irrelevant to the article. The optimizations might apply as well in any number of languages, because they all are related to minimizing heap allocations and keeping the execution pipeline lean (e.g. by minimizing function calls).

It's fairly easy to think from the title that the article is going to be something about how clever the rubyist is compared to Python programmers or how slow Python is or some such, as an intrinsic property of "rubyists" or Python.