Still niche, Rust is not up to the stuff that app developers expect in terms of tooling and D still has quite a few @safe bugs to sort out, among its current adoption issues.

Unfortunely regardless of their own reports regarding CVEs, Microsoft, Apple and Google keep turning to C and C++ for their bottom layers + managed languages, instead of going full speed in some of those alternatives.

So it appears to be the long term solution to mitigate security issues, while keeping compatibility with existing code and tooling.