This is worded too strongly but I do not know why it is being down voted. For those who feel any interpretation is warranted, many worlds is entirely credible and cleaner in some respects than Copenhagen (no collapse).
Sure, but universes are cheap. There were those who said that the theory that "nebulae" were distant galaxies should be dismissed according to Occam's Razor, because it meant vastly multiplying the number of galaxies, stars etc. in the universe. But it was a simpler theory than the idea that nebulae were some new kind of object, and it turned out to be correct.
It is clear to me that penalizing assumptions rather than "stuff" has worked out well in the past. It isn't clear to me that we shouldn't penalize stuff (or in this case, universes) at all. The fewest-assumptions version of MW seems to lead to such an explosion of "stuff" that there might well (in our optimal version of Occam's razor) exist some term that doesn't show up in evaluating nebulae, but dominates in considering MW. That said, applying a meta-Occam's-Razor for now should leave us with the focus on assumptions, and thus I think with MW.
