As long as Facebook exists, my contact list is clearly my property, and I should be able to export it.

Data just doesn't work naturally with the traditional concept of "belonging". It's natural for a physical object to have a single owner, and that owner has property rights, like you need to get the owner's permission to do anything with the object, and the owner has the right to give that object to someone else.

But for data, it's far more common for data to be about multiple people and entities, and no single one is the owner. If I buy you an Amazon gift card, that transaction involves you, me, and Amazon. Who "owns" that data? It just doesn't map to ownership.

You have to think in terms of rights for any of this to make sense. Who has the right to use the data, and who has the right to transfer the data to third parties?

It looks like society is converging on a system where some entities will have the right to use data that they do not have the right to transfer. That isn't how traditional object ownership rights work, but the rules around data usage don't have to map to the rules around physical object usage.