I would personally choose Rust over C++. I dislike the number of gotchas that C++ has and I think the language has gotten too big and complex to use safely.
In the article I linked above, the Google Android team stated:
"To date, there have been zero memory safety vulnerabilities discovered in Android’s Rust code."
Their C++ code requires more static analysis tools and fuzzers and does not have a comparable record.
If modern C++ were as safe as Rust then why wouldn't they just use modern C++? It would be a lower effort rewrite and would not need new compilers.