C# and Java have very fast compilers. A JIT is generally better for compilation speed than Go's approach, as a JIT only compiles code when it's executed. javac

C# and Java have very fast compilers. A JIT is generally better for compilation speed than Go's approach, as a JIT only compiles code when it's executed. javac and csc.exe don't do any up-front code generation, while Go 6g/8g does. Besides, I don't think generics particularly affected C#/Java compilation speed.