<i>&gt;To me, as a C# dev, this proposed change seems rather quick (let C#6 get some use first) ...</i><p>Not really.  The non-nullable references feature request has been on the radar for many years.  (E.g. this July 2009 stackoverflow post[1]).   There are also some very old MS channel9 videos where Anders Hejlsberg acknowledged that the community wants this safety feature and discusses the difficulties of implementing it.  I don&#x27;t have a link to the video but this 2008 stackoverflow post mentions a Computerworld interview on the topic.[2]<p>Non-nullable references is not a shoot-from-the-hip feature addition, and the C# team has been thinking about it for a <i>very long time</i><p>[1]<a href="http:&#x2F;&#x2F;stackoverflow.com&#x2F;questions&#x2F;411906&#x2F;c-sharp-net-design-flaws" rel="nofollow">http:&#x2F;&#x2F;stackoverflow.com&#x2F;questions&#x2F;411906&#x2F;c-sharp-net-design...</a><p>[2]<a href="http:&#x2F;&#x2F;stackoverflow.com&#x2F;a&#x2F;178090" rel="nofollow">http:&#x2F;&#x2F;stackoverflow.com&#x2F;a&#x2F;178090</a>