title: The Short Date ("d") Format Specifier does not print year with 4 digits in .NET Core on MacOS
body: <p>I want to print out a date with a 4 digit year. This should be very simple, according to MS docs. But</p>
  
  <pre><code>    static void Main(string[] args)
      {
          var sample = new DateTime(2050, 1, 1);
          var datestr = sample.ToString("d", CultureInfo.GetCultureInfo("de"));
          Console.WriteLine(datestr);
      }
  </code></pre>
  
  <p>prints <code>01.01.50</code>, instead of <code>01.01.2050</code>. Why?
  This is <em>.Net Core 2.1</em> on a Mac.
  See also <a href="https://dotnetfiddle.net/4ZSbOJ" rel="nofollow noreferrer">https://dotnetfiddle.net/4ZSbOJ</a></p>