The Copenhagen interpretation (which is, by the by, still in vogue outside of LessWrong, please stop the groupthink) allowed people to get on with their science instead of getting bogged down in its bewildering philosophical implications.
This is a perfect example of the crypto-philosophy of "we're not doing philosophy". Copenhagen is a philosophical interpretation of QM, which makes metaphysical claims about wavefunctions coming into existence and then collapsing. If anything could be called the aphilosophical approach, it would be the Feynman "shut up and calculate" interpretation of QM, but that leads to problems too.
This is not really about MWI versus Copenhagen - it's more of a meta-issue. This is about how scientists sleepwalked themselves into a philosophical theory about QM without fully realizing they were doing philosophy at all.
As far as I can tell the Copenhagen Interpretation basically is a shut-up-and-calculate interpretation. It's an operational theory that is only capable of predicting subjective-ish experimental results, and doesn't make claims about the "contents of reality". That is to say, all its predictions are of the form "if I did [EXPERIMENT] I would observe a result according to [DISTRIBUTION]". Which is somewhat respectable (although what exactly counts as an observation is naturally ill-defined, since the theory doesn't encompass the observer ...
Another month has passed and here is a new rationality quotes thread. The usual rules are: