Without Docker being so convenient for developers, it would be hard to containerize production.

One should not miss the importance of running Docker under Windows or OSX natively, with a VM running Linux tucked behind the scenes. It makes developers' experience so much nicer, and compatible across platforms. This helps adoptions a lot.

Time and again, path to mass adoption is not technical excellence, but making an important thing stupidly easy, when one has no excuses not to try.