Re: Why
"Maybe to make sure that it really was the data you thought it was?
If the meta data is broken then you don't actually know what is in the file - has someone tried to delete one file, but another has been selected due to the mixup?"
However, this is years old data, which the affected users believed had been deleted. If the issue was as you suggest, surely there would have been cries - a similar number of years ago - from the same people affected by this reappearance now to say "I deleted this file from DropBox, but this other one appears to have gone instead" ?