Why so many basic features are not part of the standard library?

In Rust, even some simple stuff like https://crates.io/crates/is-terminal requires to be imported from a dedicated crate, as opposed to other languages, like Python, where the standard kit includes a huge amount of features out of the box.

Being a newbie in Rust I am asking myself: what is the reason behind this approach? Is it a matter of time to standardize certain features or is it an intentional choice from the language maintainers?