why not let free enterprise decide the fate of this endeavor instead of...
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This is exactly what is driving these decisions. You know why Bayreuth is the only place in the world to do the full Ring cycle every year? Because mounting a 12-hour operatic spectacle is fucking expensive, and only the place with a guaranteed audience for it -- that is, an audience willing to pay a premium to see the opera in the house that was specifically built for this music -- can survivie doing it.
Make no mistake, the trends cited in TFA are not motivated by much creative interest. They are primarily motivated by cost-cutting and standardization drives, which -- you guessed it -- are the consequences of market capitalism. I mostly dislike orchestra unions -- they seriously interfered with a lot of work by myself and my colleages when we tried to compose things for orchestra that they didn't like -- but if we take your arguments and the OP's as valid, then they are protecting a legitimately valuable experience from debasement.
"Beware of programmers carrying screwdrivers." -- Chip Salzenberg