Now take in consideration that when using a single language, doing in Rust takes much longer than C++, even without taking into consideration the existing middleware engines, and support for hot code reloading.

Also that stuff like SDL and SFML are pretty much the go tool for DYI folks, and Khronos standards are all based in C and C++.

Additionally, if a managed language is good enough, and does support compilation to native code via AOT, and the middleware tooling, it makes Rust's selling point even weaker.

Which is what you see in how Unity/HPC#/NativeAOT, FNA/clang, Swift, Java/Kotlin (on Android see XR), already offer today.