The criticism here is that distributing (copying) the original image violates the non-commercial clause of the original images because someone, somewhere, might somehow have made money in some way because the dataset exists; but as they somewhat lamely acknowledge later, what counts as 'commercial' has never been clearly defined, and it probably can't be defined (because for most people 'commercial' seems to be defined by 'ewww'), and this is why CC-NC licenses are heavily discouraged by WMF and other FLOSS groups and weren't part of FLOSS from the beginning even though Stallman was in large part attacking commercial exploitation.