Rust isn't going to replace Java, but it may supplant Java in a lot of fields where one wants both memory safety and an OO language with high performance. No one is (rationally) suggesting that Rust will replace every language.
The tone of your post, however, makes it sound as though you have something against Rust, and that you're more interested in pointing out all the things it's not good at, or shouldn't be used for, rather than contributing to a constructive discussion.
> I also pointed out that Rust has to win the mindshare of C++ programmers first, before even reaching other ecosystems
Not entirely true; Rust is an alternative to C++, but it's vastly more accessible to people who've used other languages like Java, Python, Ruby, and so on, where you get types, OO, and memory safety. Instead of simply resulting in a 1:1 replacement of C++ with Rust, it may result in a minimal reduction in C++ programming and a notable increase in Rust programming which would have been done in another safe OO language instead, but at dramatically worse performance.
C++ is just a tool, as is Rust. Rust does not need to win the mindshare of C++ programmers first to become successful. It only needs to itself as a viable alternative in whatever fields people find it useful. I believe it has.
Between WASM, embedded, and even Web development, I see a lot of "mindshare" being attracted to Rust.
Rust on the other hand is not a thin layer on top of something like Coffee script. So it does not need to keep up with 'something' for decades. As long as it continues to do its current job of making systems programming safer and fun, it is going to be here for a long long time.
Meaning coming in Apple, Google, Microsoft, Nintendo, Sony, AMD, NVidia, random IoT OS vendor SDK, with bindings to all relevant OS libraries.
So far, Rust/WinRT seems to be the only thing into that direction, and given how C++/WinRT tooling support turned out, I rather wait and see.