How is Python gonna improve performance when writing a scraper, it's mostly about doing a bunch of network requests right? You could do threading in Ruby you know. Both Python and Ruby have a VM lock (GIL, have no idea what it's called in Python).
Python is good choice for scraping due to the many ready made libraries but I don't get how performance was a win over Ruby.
Node is a different story, V8 (and competing JS engines) had huge effort poured into them by Google/Microsoft so it's fast. Python never had that kind of investment afaik. We will see if Shopify can narrow the gap between Ruby and JS, I know it's a reach but they already improved Ruby performance around 25-30% since the project started (about a year?). I am optimstic the performance gap will narrow since what makes JS faster is a JIT. There is no magic here, only effort and investment which costs money.