A good example would be curlie (go frontend for curl - https://github.com/rs/curlie) vs httpie (pure python - https://github.com/httpie/httpie). Originally I used httpie for its easier syntax, but it is very noticeably slower than curlie. I presume this is why they are asking for a rust version.

Another reason is that python is a bit harder to distribute due to the nature of python packaging, where as rust compiles to a single binary.