Rust fits in a similar niche, but it has a much smaller following. Several of it's main contributors just happen to be HN regulars, so it gets more attention than it otherwise would.
C++ is not memory safe - which is one reason why e.g. Java and C# are even more "extremely widely used" than C++. Rust is memory safe, and has C++ -like performance (and arguably better than C++, with e.g. its restriction of pointer aliasing and its high-level support for things like simple parallel programming).
I was genuinely under the impression that C/C++ was being progressively phased out in favor of Rust, but looks like this is hardly the case. I guess I should probably peek outside the HN filter bubble more often...
These specification changes are usually implemented by compilers _before_ the final release date. Some features take longer, but you're usually only look at 6-12 months before being able to use 100% of cutting edge.
If anything... C++ is ramping up.
However I will keep writing C++ to go along my Java, .NET, nodejs production code, for the time being.
Rust is still lacking in IDE support, mixed language debugging, OS SDKs I generally use, integration with binary libraries, not everyone on the teams is willing to add yet another language to the mix, NVIDIA GPUs are designed for C++, and newer features make it easier to write safer code, in spite of its C underpinnings.
Yes it looks phylosophically nice, but out of the language purist&geek, managers will not care if you are allowed or not to shoot you in the foot, they'll only care if you can deliver or not in due time.