I run a nonprofit group that maintains a similar but different database, ours focuses on identification of heritage varieties, I.e. apples that existed pre WWII. We're in the PNW so we also have catalogs of where they were sold to make their way to us, etc, as we identify trees in old orchards.

I've learned some interesting stuff along the way, like that English varieties keep showing up in eastern Washington because English nurseries shipped to Vancouver in the late 1800s.

Our apple database is here: https://heritageapplecorps.org/varieties/

https://applerankings.com/

I wonder if there is a way to report issues. We have several apple trees of different varieties, and as I was playing around with the harvest period calculator, I entered the peak harvest of one of our later ripening varieties, and asked it to calculate the harvest time for our earliest ripening variety. It told me that peak harvest would be in December. It's actually (as the description for the variety notes) in June/July. So either there is an issue in the harvest period for that variety, or else the calculator is messing up somehow.

Apples have not, and I think that's great.

Is this because other fruit varietals are generally not significantly different? Is there some special sauce behind apple distribution?

I use this site for many years: https://www.orangepippin.com