C# will be around 'forever'. It's robust, well-supported, well-documented, and with Mono / Xamarin works across many platforms (including iOS and Android). I ha

C# will be around 'forever'. It's robust, well-supported, well-documented, and with Mono / Xamarin works across many platforms (including iOS and Android). I haven't experienced inherent memory leaks as you have described (10+ years of heavy use). Performance limitations are more tied to IO (disk, network etc) than the language. That said, this isn't an either/or question. One can learn more than a single language at a time. A decent programmer, IMO, has knowledge of several languages, and there is no disadvantage at all in making one of those C#.