That's not true, Java generics are not just syntactic sugar.
> They don't add anything substantial.
They add parametric polymorphism and type safety.
> You can use Object (or another bound type) everywhere you're using generic type.
Only if you go out of your way to do so, and ignore warnings. This has less to do with how generics work in Java and more to do with the fact that Object can be explicitly cast to another type and vice versa.
> You can do exactly the same thing in Golang. Just use interface{} everywhere and add few casts where needed.
That's not true, Java generics are not just syntactic sugar.
> They don't add anything substantial.
They add parametric polymorphism and type safety.
> You can use Object (or another bound type) everywhere you're using generic type.
Only if you go out of your way to do so, and ignore warnings. This has less to do with how generics work in Java and more to do with the fact that Object can be explicitly cast to another type and vice versa.
> You can do exactly the same thing in Golang. Just use interface{} everywhere and add few casts where needed.
No, it's completely different.