We're actually even at the point where Java has added language support for sum types and pattern matching!
Java is also the most prominent example of a lack of null safety. Once Java gets around to fixing that in the next century or two, then Go will really be behind.
* It's name
* Nils
* Pattern matching
* Enums / Sum types
* Generics
* Error handling
Other ecosystems have recognized that pattern matching and sum types are the way forward as well as null safety.