I wonder why they landed on the "deleting oldest content first" format. The oldest items are the ones less likely to be backed up by users.
They had lots of options, including removing original quality images and just keeping resized images, archiving the photos off-platform and charging users to restore them from the archive, or deleting the photos that had the least views.
Not sure which, if any of those, might be a better option, but the one they went with has lots of downsides too.