I know that Rust provides some additional compile-time checks because of its stricter type system, but it doesn't come for free - it's harder to learn and arguably to read
Ownership/borrowing clarifies whether function arguments are given only temporarily to view during the call, or whether they're given to the function to keep and use exclusively. This ensures there won't be any surprise action at distance when the data is mutated, because it's always clear who can do that. In large programs, and when using 3rd party libraries, this is incredibly useful. Compare that to that golang, which has types for slices, but the type system has no opinion on whether data can be appended to a slice or not (what happens depends on capacity at runtime), and you can't lend a slice as a temporary read-only view (without hiding it behind an abstraction that isn't a slice type any more).
Thread safety in the type system reliably catches at compile time a class of data race errors that in other languages could be nearly impossible to find and debug, or at very least would require catching at run time under a sanitizer.
Do you think Zig is a valid challenger to Rust for this kind of programming?
Almost none of the Rust features discussed in this subthread are present in Zig, such as ownership, borrowing, shared vs. exclusive access, lifetimes, traits, RAII, or statically checked thread safety.