I will start out by bluntly stating that if someone have never seen a ambrotype, dagguerotype, platinum, carbon, AZO contact, up close (yes, the actual physical print) then they really have no business discussing the merits or subject matter of such processes. Basing judgements on a computer monitor jpeg is comparable to saying you like or dislike a new CD not by listening to it but by listening someone hum or sing it for you. To make judgements in such a way makes the person a fool.
I will agree that it is easy for the practitioner of alternative and ULF photography to get trapped into a box as far a subject matter is concerned.
However, it is the process that adds a certain dimension to the subject matter that allows a platinum print or ambrotype to be unique and in many ways exceptional to their silver gelatin cousins. And of course its all subjectve. I can find an enormous amount of pleasure in a simple still life collodion of a flower in a vase or a paltinum print of a row of hats hanging on an ancient wall.
ULF and alternative processes are just variations on a medium that lend themselves more to some ideas then others. Done well, even with what may be considered by some boring subject matter the prints can be stunning.
But like I said it is all subjectve. I can go to flikr and find thousands of really bad photographs. They all want to be Kertesz, Bresson, Frank or Winnogrand. I mean have we not covered all the bases already? It's all boring when considered in the context of 150 years of images that have come before.