Earlier quoted context omitted.
I remember reading somewhere that Go was originally intended to take over a lot of projects that are currently C++, and that it was kind of a surprise that more Go programmers ended up coming from languages like Python. If that's right, it might be fair to say Rust and Go were "originally" competitors, even if they aren't as much anymore :)
As a C/C++ developer that doesn't surprise me at all. I looked at both Go and Rust and I'd go with Rust if given a choice between the two.
It might be that they underestimated how desperately people had already moved away from C/C++ if they had any choice at all :)