I'm actually pretty amazed at what the Javascript VM people have done in the past decade. It's way more than I ever expected.

As far as the carbon footprint, well, yeah, it depends. At Google I remember a friend talking about how he cringed whenever he added more code to the pipeline that ingests the entire internet. He said that he wondered how much extra carbon was release into the atmosphere just because of his stupid code.

As for numpy, we are seeing that loops are stupid and Iverson and APL were right. :-)