Until .NET Core provides support for many of the .NET Framework APIs still lacking from .NET Standard 2.0, many companies won't consider it "enterprise grade".
Examples on our case, WPF, WCF, ODP.NET drivers for ADO.NET.
Examples on our case, WPF, WCF, ODP.NET drivers for ADO.NET.
As far as I know, there are not plans for cross-platform GUI on .Net Core. And WPF is pretty much a dead technology.