Há alguma razão para os backups diários apresentarem redução no tamanho?

Sam, I’ve been thinking about why our backup is so big when we don’t really have that many images uploaded… I think it might be because of the welcome DiscourseBot.

From what I remember, it asks users to upload photos to help familiarise them with the upload system. I’m wondering, would it be a good idea to have Discourse automatically delete these PMs (and all uploads inside them) after 2 or 3 months after registration?

It seems a waste hosting these uploads when they are not going to be seen by anyone and are effectively for testing purposes only… what do you think?