I don't know what you're saying about Zig. I have no predictions about that language's success, I just think its design is very interesting.

Those examples of Rust use by industry giants are a red flag for its adoption, because they look nothing like adoption by those very same companies of languages that ended up popular. Obviously, non-zero usage is something, but the rate and extent of adoption for what is now a fairly old language is exceptionally low compared to languages that ended up making it.

Such an unusually low adoption rate means that it will take another two decades for Rust to pick up even 50% of the low-level space (assuming some positive second derivative). It could be less if the rate suddenly picks up, but it could also be never if other competition enters the game in all that time. Nobody needs to drop Rust for competitors to have a chance because only a small minority is picking up Rust in the first place. On paper, Rust seemed to have better chances than Go in its market segment, but it's doing worse.

Rust is now at the age Java was when JDK 6 came out, and it has maybe 1-2% of the market and 5-10% of the low-level segment. That is not where Rust's believers expected or hoped it would be at this age. Could it somehow succeed in a way that's different from all successful languages before it? That's certainly a possibility, but I don't see any indication for why anyone should bet on that unusual thing happening.