I can't help but feel that given the requirements laid out in the article Nim would be a more suitable fit for their goals over Rust. I do think Nim really nails great performance with a very clean and straightforward syntax, certainly easier for someone who only works in Python to pick up over Rust.
Nim would be a nice option if the ecosystem were even half as developed as the Rust package ecosystem.
Nim has plotting, dataframe, matrix libs and even a fully featured machine learning library, I don't see the reason why it can't be used, especially by scientists.
https://github.com/Vindaar/ggplotnim https://github.com/unicredit/neo https://github.com/mratsim/Arraymancer