Embedded, low power, real-time, drivers, high performance computing, low-level kernel, legacy, and so on... The alternatives you give are not really the best e

Embedded, low power, real-time, drivers, high performance computing, low-level kernel, legacy, and so on... The alternatives you give are not really the best examples either. C# is only a viable development platform for serious/professional work if you're targeting Windows, and if there is one language that doesn't do anything better than the many alternatives that compare favorably to it, it would be Java.