You need type info, if the language has its own type system which has more information than Rust. Imagine you have machine code generated by compiling a C prog

You need type info, if the language has its own type system which has more information than Rust. Imagine you have machine code generated by compiling a C program and now want to figure out what struct some function takes as an argument. As you go down towards machine code you lose information that you cannot easily recover. Solving all of these issues is also only practical, if the Rust developers themselves cooperate. It seems to me the very purpose of creating a new language, is in freeing yourself of the limits existing ones have. Building a new language on technology that are restrictive doesn't really make sense from that perspective.