So, maybe this is a train of thought that won't really go anywhere, but Hoid frequently (I want to say always, but to be safe I'll stick with frequently) calls shard vessels by their name, not the shard they hold. We see this pretty often.
So, here's me putting on my aluminum foil cap...
Is Hoid consciously thinking of them as their vessels on purpose? We have a few examples of things existing in the way they do because people perceive them that way (spren, as one example). Is Hoid doing this to, even slightly, combat the fact that vessels eventually become more like the shard they hold?