It's not had time to stabilise. Many of the multi-platform features are still developing and there's some stuff in there that can trip you up if you're just reading the documentation.

A big problem I ran into recently is that the documentation for some methods indicate they can throw a "PlatformNotSupported" exception but don't link to anything that lists which platforms/versions actually support the method.

Some new features like single file executables will break existing code in subtle ways, a common method of getting the application directory was to use Assembly.GetExecutingAssembly().Location, when running as a single file executable that returns an empty string.

I still think it's a big improvement over the older .NET Framework stuff that I'm mostly using, but I can see why it isn't so appealing to the Java crowd.

25 years of momentum.