Maybe. Certainly it's not the case that Rust is just blanket 5-15% faster than C++ for tasks, not even in the vague hand waving way that Python is typically say 10x slower than C++ or Rust would be.
However, there are some ways that I'd expect similarly capable programmers are likely to often produce faster Rust code than C++ and much fewer ways I'd expect the opposite, so it's not a surprise when this work results in a small unlooked-for performance improvement.
However, there are some ways that I'd expect similarly capable programmers are likely to often produce faster Rust code than C++ and much fewer ways I'd expect the opposite, so it's not a surprise when this work results in a small unlooked-for performance improvement.