Some people are so focused on categorical thinking that they are missing the forest for the trees.
The colors are a means of describing an observed outcome -- in Node's case, callback hell, in Rust's, 4 different standard libraries. Whatever it may be, the point is not that there are colors, it's the impact on there being colors.
> But there is a catch: with this new I/O approach it is impossible to write to a file without std.Io!
This sentence just makes me laugh, like it's some kind of "gotcha". It is the ENTIRE BASIS of the design!