The only benefit JS has over Go for adoption is that people are pretty much forced into using JS or something that compiles into JS.
I think Go's take on concurrency is less confusing than callbacks. It's not like the language is massive and close to impossible to learn.
People had a ton of time to create interesting web dev related libs for Go but no one has. There's only a mix of libs that are pre-1.0 (dead), really low quality (missing extremely critical things), or bad performance because they haven't been tweaked under load because no one is using them.