I live in the "Apple Capital of the World", had to learn about apples my whole life. I'm not sure its a fair to make blanket statements about red delicious apples as many are not cloned/grafted, so the taste varies from producer to producer. The big name varieties of apples now are all copyright/trademark and grown via grafting, making output control much easier. Many of the older red del orchards are old and no longer profitable due to modern day orchard planting and management being much more advanced. As those orchards get replaced they get replanted or grafts from a currently more profitable variety are put into them. A reasonable amount of new varieties are growing on stumps/roots that once produced red delicious fruits.

Rave and Ambrosia are the two variants Stemilt is pushing hard these days.

the average now is around 12 years before they switch the varieties and put new grafts on a stump. seven years to get back to full production size, 5 years of product and then switch. the apple varieties being marketed today have been in the works for near a decade or more.