I think it has become EASIER: for instance, since C++23 Rust-like move semantics can be used, which provides the compiler with extra information that can be leveraged for the generation of better code.

Or take constexpr - it permits to move computations to compile time that are complex and in older versions either had to be done at runtime, or an ugly workaround had to be used (e.g. assigning a mysterious literal pre-computed in another run or by hand).

> C++23 Rust-like move semantics can be used

What C++23 feature allows that?