Two additional points:
1. Tooling (as an extension to the mentioned IDE support point). Zig and Rust are both praised for their tooling and I think rightfully so. The C/C++ interop story and the cross-compiling story in Zig are great. From the standpoint of a working practitioner though I think Rust is way ahead. Not surprising given that Zig is much younger, but something to keep in mind.
2. Compile Time Stuff: Here Zig is praised and Rust not so much. I think this is undeserved. Rust has much higher aspirations for their compile time features, namely that outcome must be identical regardless when the code runs. This is a very useful property but makes the task much harder and fundamentally incomparable with Zig comptime.
Zig comptime feels easier and more effective in practice. I've had some fun const evaluating some stuff in Rust, but I needed to use a bunch of annoying imperative hacks because so much of the functional stuff wasn't supported in const context back then. It's probably a bit better these days.
For one of my crates I needed to have a build script make a bunch of lookup tables as separate files for me to `include_bytes!` because at the time I couldn't generate a bunch of floating point conversions in const.
Are you saying that you think that Zig does not produce identical outcomes for comptime code regardless of when the code runs? What do you mean?