That's a design choice.

Less implicit means safer but also more verbose and more cumbersome to write.

Rust priorities safety over everything else, also over productivity too in some case.

Absence of function overloading and automatic type conversion is a good example of that in Rust.

Is it the right choice ? Only time and multi-million line codebase will tell us.

Rust doesn't have function/operator overloading yet or it won't have it at all? I am vastly for clarity and simplicity over vague, implicit stuff but doing e.g vector operations can get very unreadable very quickly without it.