Just to avoid confusion among readers, I want to distance myself from part of Vladimir_M's position. While I agree with many of the points he's made, I don't go so far as to say that CPI is a fundamentally flawed concept, and I agree with you that we have to pick some measure and go with it; and that the use of it does not require its caveats to be restated each time.
However, I do think that, for the specific purpose that it is used, it is horribly flawed in noticeable, fixable ways, and that economists don't make these changes because of lost purpose syndrome -- they get so focused on this or that variable that they're disconnected from the fundamental it's supposed to represent. They're doing the economic equivalent of suggesting to generals that their living soldiers be burned to ashes so that the media will stop broadcasting images of dead soldier bodies being brought home.
I wouldn't be in a good position to determine if it's lost purpose syndrome since I'm an insider, but I would suggest that path dependence has a lot to do with it.
Price indices are produced by governments, who are notoriously averse to change. And what's worse the broad methodology is dictated by international standards, so if an economist or some other intelligent person comes up with a better price index they have to convince the body of economists and statisticians that they have a good idea, and then convince the majority of OECD countries (at a minimum) that their method is worth the considerable effort of changing every country's methodology.
That's a high hurdle to cross.
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