When you buy them at the farm, you are just buying "pineapples" the way they grow them. They all look the same. The flavor is some combination of the genetics, the local growing conditions, farming methods and the level of ripeness when they are picked. Most people that try them tell me it's the best pineapple they've ever had and I agree that a good one can really be off the charts.
It's kind of the luck of the draw how the ripeness and flavor combine to hit your palate. And I think this is a topic that really bears more discussion, what is the actual product here, genetically? I am pretty sure he started off with mostly MD-2 plants and I think some local wild types mixed in. Is there some element of genetic drift or recombination there? I'm not smart enough to speak to that, but every pineapple I've eaten from that farm tastes a little different. Some "just" taste like an improved/sweeter/fragrant supermarket pineapple and others have more flavor excitement with notes of vanilla, honey, spice and pina colada/coconut. And all points in between.
If I remember correctly, most of the fruit sold are regular MD-2s, the variety you get in the grocery store.
Only around 10-30% of the fruit seem to be the other varierty and have the coconut flavor.
So most people probably ended up receiving regular MD-2 fruit and not the "Dellerman" variety.