My position on shadowing is that it's a thing where different projects can have different opinions, and that's fine. There are good arguments for allowing shadowing, and there are good arguments for disallowing it.
This is another big difference between Rust and Zig. Rust lets you have it both ways with configuration. Zig places much more value on being able to read and understand any Zig code in the wild, based only on “it compiles”. Rust’s “it compiles” gives you lots of information about safety (modulo unsafe blocks), but very little about certain other things until you’ve examined the 4-5 places which might be tweaking configuration (#[attributes], various toml files, environment variables, command line flags).