.NET structs never have reference equality, because structs are value types. Here is a fiddle https://dotnetfiddle.net/AvazwY

public class Program
{
    public static void Main()
    { 
        var foo = new Foo();
        var bar = new Bar();
        
        Console.WriteLine(object.ReferenceEquals(foo, foo)); // false
        Console.WriteLine(object.ReferenceEquals(bar, bar)); // true
	}

	public struct Foo
	{
	}
	
	public class Bar
	{
	}	
}