Curtis hires four composers

John Borstlap says:

Interestingly, this is true, but only within the territory of contemporary music, say: post-WWII-music.

The ‘old’ repertoire though, shows that there are indeed standards, depending on context. That perception in this field is also mainly subjective, does not mean that some objective standards cannot be detected or described. Every product of every culture answers certain patterns that are deeply embedded in the human psyche, and the better a work of art makes use of these patterns, the better the work – technically, aesthetically, and in terms of meaning. These patterns are patterns of mathematical order, the same patterns which have determined everything in nature, and they have much to do with the experience of beauty.

https://neurosciencenews.com/?s=Mathematical+beauty

There are certain aspects of art that seem universally appealing, regardless of the environment or culture in which people grew up – indicating that there are universals in the field of aesthetics, i.e. objective standards, however subjectively interpreted:
‘The human brain is wired in such a way that we can make sense of lines, colors and patterns on a flat canvas. Artists throughout human history have figured out ways to create illusions such as depth and brightness that aren’t actually there but make works of art seem somehow more real. And while individual tastes are varied and have cultural influences, the brain also seems to respond especially strongly to certain artistic conventions that mimic what we see in nature.’ (From CNN Health: ‘What the brain draws from: Art and Neuroscience‘, 15 September 2012.)

https://edition.cnn.com/2012/09/15/health/art-brain-mind/index.html

All of this indicates that, probably, basic universal aesthetic laws do apply, and that they play a role in our appreciation of art. This means that although there are subjective interpretations of art, what they interprete are existing universal aesthetic laws, embedded in human nature.

So, if we develop our perceptive faculites, we can trust our aesthetic judgments. And this is helpful to make sense, for instance, of this, product of a mathematician:

https://www.youtube.com/watch?v=rpCYdmue62o

Xenakis applied mathematical methods but bypassing human perception, in an attempt to render ‘music’ objective, rational. So, searching for objective standards in a way opposite of human nature. The result is crapulous, in any technical and aesthetic sense.

And what about ‘marketability’ as mentioned in the comment?

Orchestras and opera houses have different ways of deciding which contemporary music to play. Where they simply follow fashion, that is also the result of post-WW-II composers leaving any artistic standard behind.