Fair criticism, it's my main gripe with Go as well - it's not strict enough when it comes to e.g. nil, enums, and type safety. Annotations are supported but they're just strings. Projects require additional tooling / linters to check for things like unchecked errors and many more "gotchas" that I think could (should?) be part of the compiler or standard tools. Trivial example, Go's compiler will error when you have an unused variable, but won't if you reuse and overwrite an error variable a dozen times and only handle it once.

But on the other hand, I suppose it makes it a bit more pragmatic - less checks makes for a faster compiler, and fast compilation was/is very high up in the language's requirements and motivation. If you want / need more strictness in your language, there's Rust, Java, C#, etc.