Which would be correct, considering that ownership implies full and complete right of dominion over said entity, which you simply don't have. You could be locked out of your account with no means of getting back access, you can delete your data but have no guarantees that the data has been deleted, Google may create 'derivative works' on your data (see the terms of use) without your permission or will provide data about your account to authorities, etc.. That is not ownership, that's renting.