golang doesn't really compete with rust, but it's more like a faster python/ruby/js. You can see this by the companies that have moved over from those languages to golang. Hype definitely plays a role, but also the perception that it's quick to pick up, and does decently well when it comes to performance.

> The real question is, why is there not a “Go but designed by sane people” language?

The fact is that the JVM and .NET platforms would almost surely do better for anything that golang is considered for, but there's a lot of hype and companies want to attract programmrs.