There will be eventually only one faction left using C++ — the legacy too-big-to-refactor one.
The other faction that has lost faith in WG21, and wants newer, safer, nimble language with powerful tooling is already heading for the exits.
Herb has even directly said that adding lifetime annotations to C++ would create "an off-ramp from C++"[1] to the other languages — and he's right, painful C++ interop is the primary thing slowing down adoption of Rust for new code in mixed codebases.
[1]: https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2024/p34...
> newer, safer, nimble
"newer" is hopefully a non-goal.
Unfortunately, an option that is both safer and nimble doesn't appear to exist. I'm still hopeful, but at the moment it looks like rust is our future. A fate only marginally better than C++.
Everything out there is nimbler than C++. So you only have to select for safer to get those, and anything with managed memory and Rust are safer. (Not an exclusive set, but you'll need to actually evaluate other options.)