Pears very often do this if unpollinated. Could that explain it in your case?

Wish I could help you, but I am having the same issues. My trees are in the ground and I have four each of Luscious, Parker, and Patton. Every year they have flowered I have had the same result. The bees work them heavy, so it can't be lack of pollinators.

Not sure how far along your fruit are getting before the drop, but maybe too heavy a crop? you said it had lots of blossoms, and they all set, maybe thinning would have helped? still, I can't see them all dropping.

Do you spray? some sprays can act as a thinning agent if you spray within 30 days of fruit set, label should say so.