It may be true in the literal sense that "the developer talent pool for C++ is much larger than Rust" in that there are more C++ developers than Rust developers

It may be true in the literal sense that "the developer talent pool for C++ is much larger than Rust" in that there are more C++ developers than Rust developers, but if I can plug my own research a bit: at least for open source projects, rewriting in Rust seems to increase the number of contributors, across all experience levels. https://cypherpunks.ca/~iang/pubs/gradingcurve-secdev23.pdf https://cypherpunks.ca/~iang/pubs/gradingcurve-secdev23.pdf