Yup. It turns out that Google internally uses C++ for developing web applications (or at least HTTP API endpoints), which nobody on the outside quite internalized. So Go is a perfectly reasonable C++ replacement from the point of view of Google, but doesn't hit the majority of use cases outside, and it feels rather more like a compiled competitor to Python/Ruby/etc. to most of us on the outside.
Also, until about a year before 1.0, Rust had heavy focus on lightweight concurrency (à la goroutines), a garbage collector built into the language (or at least plans for one, complete with syntax), a mandatory runtime to manage those things, etc. You had to give up on the standard library if you wanted to use Rust code as a shared library in non-Rust programs. That changed fairly rapidly, and the last bits of that (like runtime removal) only hit a few months before 1.0, so people's first impressions of Rust were much closer to that of Go.
They're very different languages today. It is technically true that for both of them they are better than C++ for some things people have traditionally used C++ for, but once you get beyond that they're not that similar.
