While it's certainly not true of every older person, many of the older people I know do not seek out new music at all. Previously, many of them were basically no longer in the "music market" aside from tours and some terrestrial radio in the car. They owned all the albums they liked and they listened to them, and that was that.
All of which is to say that I'm not sure that young people are listening to drastically less new music than before.
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The decline of the Grammys largely mirrors the decline of awards shows for other media. I'm not sure it's a proxy for how much less interested in new music people are, rather than a lack of interest in the industry anointing meaningless winners to itself in an age where there's plenty of people who's opinions that are more relevant to me that I can look at.
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Some other critique:
- Half the article is about streaming (a new service/technology/business model), then we're complaining about not enough new technology/R&D....
- Vinyl is having a resurgence as a physical format because physical formats are completely unnecessary now to listen to music, so the most tactile, interesting one is surviving. It's arguably the exact opposite of stagnation, given that the image and market for it has completely changed.
- I don't agree that record stores are particularly caught up in the same time warp. Extremely limited vinyl pressing capacity that hasn't kept up with demand is the primary issue limiting new vinyl releases and crowding out smaller acts, not a lack of willingness to stock newer artists on shelves. They're selling every record they can get produced, to be blunt. Additionally, the Apollo Masters fire in 2020 caused major and ongoing disruption to vinyl record production.
- Extremely few people care about musical holograms, these are certainly not any significant % of the market or doing anything for "making it harder for young, living artists to compete in the marketplace".