I'm confused by your statement, Jeremy. The 'alas' suggests that you don't think something is poetry just because the author thinks it is, and yet you then say that 'it's all relative.'
Whatever you meant, I don't think it's relative. On the surface it may seem to be, in that someone may read more than the first lines of a poem because of being drawn to it in some way. But deep down a poem will be saying something in the only way it can be said, otherwise why not simply write what you want to say in prose?
We all at some time have nightmare, drink-ridden, mentally jumbled thoughts to which only we are privy. But if we want others to understand us and appreciate those thoughts that are precious to us, then we have to couch them in a manner that will be apprehensible by those we wish to inform, entertain, reach, or whatever is our purpose in writing.
To me poetry is more than an indulgence, it is also a responsibility. We have a responsibility to ourselves to describe our mental experience as accurately as possible. A poem may seem to be distasteful to the reader, but so long as it touches him or her in an authentic way, a way that reveals our experience to him in its totality, it will be a poem. If it is merely distasteful, then the effort has been wasted.