Having dev evangelists presenting cool shit gets people aware of your platform and it's free marketing, the best kind.
Further, Java, Python, Ruby, Obj-C, Android and C# isn't complete. [0] JS for browser front-end and node back-end is clearly missing or third-party. A somewhat smaller shop, Segment.io, has all of those and PHP and Clojure. And a metric ton of integrations comparatively. [1] [2]