While it may be hard to show that Java's demand has decreased - and overall it may well not have since many companies which were using Java will continue to do so just by inertia - but for the latest generation of programmers, specially ones focused on ML / Data Science, Java feels like ancient history
Clearly both Rust and Zig tackle tough problems and implement solutions that will have trade offs. I don't think the top answer to a post talking about Zig's advantages should defensively try to point out how things could be different in Rust - if only you knew exactly what to do - instead it would be nice to see more discussion about other areas where Rust is perhaps better suited than Zig. For instance, you Rust clearly handles memory/pointers better (?), while maybe Zig is easier to learn?