My concern is that without new works ballet becomes a dead language like Latin: a relative handful of specialists pore over the old masterworks, a few students learn to read them -- maybe write a sentence or two themselves for practice -- and the real conversation takes place in another language. There is general agreement that The Aeneid is a touchstone of Western literature, but hardly anyone reads it in either the original or in translation and any influence it has on the culture at large is at a two or three degree remove.
Or maybe ballet turns into something like the Broadway musical, a once vibrant form that is now mostly for tourists and nostalgic aficionados, with the only over-amplified revivals and "new" works like "Mama Mia" on offer. We might not be lucky enough to get Noh.
Before Balanchine & Ashton became "set in stone greats" they both worked in commercial theatre, in Broadway, Vaudeville, The Negroe Revues, Films, commercial dance - it was their take on how populism could enrich ballet that moved them forward to become what they were.
Nor were they alone De Mille, Holm, Falco, Massine, Petit - none of them were adverse to exploring the wider field and using their findings to enrich creativity.
What will make ballet die and wither is viewing it as rarified, too precious to be tainted by base popular entertainment forms. If what it is is a language that can't be deciphered in any other format or form than classical purity it will be Latin; a dead language of interest to historians, librarians and antiquarians.
In their lifetimes the greats who now are viewed as establishment were straining to break free of the weight of the past, to find how classicism was relevant to creating within their time and space and for the society in which they lived - it's what artistic progression is about.
Balanchine & Ashton were lucky they had nascent companies and space to create as much as they wanted, to make mistakes and lived in a time when ballet was seen as relevant, or at least more relevant than it is now.
But to yearn for a past which probably never truly existed in the first place, to attach to it a quality of a halcyon nirvana to aspire to is a death knell. If ballet's apogee is historical and it's salvation as an art form is nothing but looking back and regressing,then perhaps it'll deserve to be relegated to the forgotten & dead languages file.