All of your questions are addressed in the article.
> Why Rust? Why not Idris? Why not Haskell?
it can easily call C code
it can easily be called by C code (it can export C compatible functions and structures)
it does not need a garbage collector
if you want, it does not even need to handle allocations
the Rust compiler can produce static and dynamic libraries, and even object files
the Rust compiler avoids most of the memory vulnerabilities you get in C (yes, I had to mention it)
There are quite a few great books on stable information. To name a couple: Knuth's Art of Programming, Structure and Interpretation of Computer Programs, Advanced Systems Programming in the Unix Environment, the dragon book.
Why should I own them physically? Well, I find physical books more comfortable to read than digital ones. They lack text search, but being able to have it open on my desk next to my computer is handy. Not to mention the sleep hygiene issues from using a screen before going to sleep.
> Why Rust? Why not Idris? Why not Haskell?