One aspect that comes into play is shelf life / freshness of the apple. I normally find Golden Delicious apples to be completely devoid of taste. But they keep a long time so chances are the ones I come across are months old.

I was at an apple orchard a few years ago and encountered an awesome apple, enquired as to what was planted on that row and it was Golden Delicious. I triple-checked because it was a completely different taste than I expected.

It would seem that taste doesn't keep once the apple is picked and it becomes bland over time.