In my experience, it depends on the kind of development. For hobbyist and open source development (myself included) it is right: C++ is just legacy.

But in the professional industry, C++ is still alive and strong. Lots of professionals are comfortable with C++ and don't want to ear about Rust or anything else. All my customers paying money are using C++. Even for new projects.

That said, I can see a growing interest for Rust in the industry as well. So this might change really soon