How many? how many didn't use Go because it lacked of a sane type system? because Go relies way too much on runtime behavior (AKA type switches and reflection) to be called a modern statically typed language. In all my time using Java I never had to cast something once or use reflection, or to do a type assertion, all these are common practice in Go, especially when the std lib is now getting API like Context.Value(interface{})interface{}.
This isn't PL theory, these are flaws that aren't going anyway and will become more apparent as users will have to maintain all that "productive Go code" written 5/10 years ago. With Go the developers basically do the compiler's job manually. These problems are absolutely not going away, and people will write about how they ditched Go for these reasons.