You are technically correct ("The best kind of correct"). However, the only places where Silverlight still enjoys any use is, as far as I can tell, in streaming services to PC and Mac (e.g. Netflix) - and in those places, the only reason they preferred Silverlight to Flash or HTML5 video is .. DRM.
So practically, Silverlight is on life support maintained by DRM. If e.g. Netflix decides to drop DRM, you can bet they will stop using Silverlight and switch to something more portable (e.g. Flash or HTML5 video).
Statistically, Silverlight use has everything to do with DRM.
(weak analogy: Guns don't have anything to do with causing bodily damage. They just shoot projectiles at high speeds. In this thread, we are discussing personal safety)