This is where .NET Core gets confusing. They're just able to run on the .NET Core runtime (versus the "full" .NET Framework). WPF uses DirectX heavily, so it's

This is where .NET Core gets confusing. They're just able to run on the .NET Core runtime (versus the "full" .NET Framework). WPF uses DirectX heavily, so it's not like Microsoft just ported DirectX to non-Windows platforms.