[dhfhduk]

I lived not too far from where Red Delicious was originally bred, and I can say from personal experience the original Red Delicious is not the Red Delicious that is typically sold in the grocery store.

Of course, I've never had the original one, but the heritage Red Delicious apples from multiple small orchards within a certain radius of where it was developed all taste totally unlike the ones in large groceries elsewhere in the US.

The ones from Iowa you would probably recognize as Red Delicious if you were told that, and if you were not told their identity you probably wouldn't. They're much smaller, rounder, more variegated in color, and have a much more complex flavor. Many people would probably guess McIntosh, but probably would say they have no idea.

My experiences have left me with the strong impression that some kind of subsequent genetic drift/inadvertent selection occurred, or that there's such a dominant set of horticulture protocols with the apple that the original characteristics of the apple have been washed out.

[stouset]

I don't think circumstances around your anecdote leave room for it to be factual. "Red delicious" isn't simply a breed of apple — they're all trademarked clones. The offspring of an apple tree won't produce anything like the fruit of the original apple. In fact, the overwhelming majority will be inedible and only suitable for cider. Genetic drift isn't really plausible because there's no mechanism by which these trees would drift genetically.

New apple strains are, as far as I know, not really bred for. They're found in the wild.

I may be wrong, but I'm pretty confident that an apple that isn't a strict clone of red delicious can't be marketed as a red delicious. It's also possible that growing conditions now have changed enough to alter the fruit, but I'm not positive that it would be a large enough difference to notice.