> C++ is still indicated for systems that are optimizing for performance

The only evidence I've seen for this is that people with a vested interest in my believing this keep saying it is true. That's the exact same evidence I have for Trump having triumphed in Iran. Do better if you want me to believe you.

> since it intrinsically requires a lot of "unsafe" constructs.

This is an excellent reason to choose Rust. The whole point of Rust's technology is to enable you to encapsulate the tricky difficult part of the problem so that people don't blow their foot off working on the mundane parts of the software. And the truth is there are always mundane parts of the software.

I'm feeling generous so I'll add more here: Vec<T> illustrates how this works. This is a growable array type, C++ has std::vector<T> for much the same concept. But inside Vec<T> this encapsulation is used heavily so that there's a RawVec<T>, which doesn't care about knowing how many things are in the growable array, only about its capacity, then a RawVecInner which doesn't even care what things we're keeping in the array, it's just an appropriately large container for whatever it is, that RawVec<T> remembers what T is if that becomes important - and then a Cap which doesn't even contain things, it's just in charge of being able to represent the capacity correctly while having the same shape as "just" an integer but not always necessarily working like one.

Vec<T> is entirely safe to use, very pleasant, no danger. But internally it's extremely sophisticated, hence the layers of different types encapsulating different pieces of the problem to make a growable array type with excellent performance.

In real world systems, Java can beat programs in compiled languages like C++ and Rust when it comes to throughput and even latency.