I don't worry about the multiplicity of interpretations for QM, under determination is unavoidable in physics as Fredrik pointed out about SR and GR. I'll happily live with such multiplicity as long as each ontology is consistent with all of our theories of physics. We don't have that situation now because violations of Bell's inequality imply causal and/or constitutive non-locality while GR is local on both counts. This incongruity prompted Smolin to write (The Trouble with Physics, 2006, p 9), "This is probably the most serious problem facing modern science," and (p 10), “The problem of quantum mechanics is unlikely to be solved in isolation; instead, the solution will probably emerge as we make progress on the greater effort to unify physics.” That remains to be seen of course, but those of us in foundations who subscribe to this attitude are hoping to find clues to unification by considering various interpretations/ontologies for QM. The study of QM interpretations serves as a basis for the study of unification in that sense.