Pu-erh tea had many tea drinkers addicted to its aged, decomposed flavor. Other aged teas also got more notice, oolong has its share of followers, aged green teas surface here and there too.
Who has the most stock of aged teas? Who has the financing and storage to hold and house teas for a long period of time? None other than China natural products import and export company, tea subsidiary, even today. Before privatization of tea manufacturers, communist party owned tea company house and control all tea productions via purchasing teas from local farmers. Farmers "sold" their productions to the government, some might leave a small quantity for their own collection. Majority of aged teas are still within control of the Tea subsidiary of local provinces. Only small quantity is available on the market.
Aged teas by farmers can be either intentional or circumstantial, however majority of the teas own by the government are most likely aged circumstantially.