Maybe this could all be saved by adding an extra class to the tags ? "Possibly Suggestive Semi-clad Female/Male Human Adult "  :) To my mind, clothing is clothing,  .Nude means NAKED..ie..NO Clothes. There are unfortunately some people to whom even the 'suggestion' of nakedness is offensive..the obsessive ones go LOOKING for pics to be offended by:( Now..if you allow them to be arbiters of 'public taste/morality' , we are in trouble.  The figure in question is very clearly clothed..maybe there are unfortunate 'reflections/shadows..but if you have to go enlarging pics/reducing resolution, etc to even NOTICE them..isn't the complaint a bit ridiculous ? Maybe the Mod involved felt they had to acknowledge the complainers request, maybe they could have done it a lil better..but unless we hear..(and as general members we have no right to hear of private communications between mods and individual members)...the reasoning from the mod involved, we won't know. 
Is there a 'standard form letter/email' form that the mods use to correspond with members over possibe TOS violations ? If so, maybe THAT is the problem in that it automaticaly adds a 'warning' when it's not really justified ? Form Letters don't really cover all circumstances.
If you want TOS violations..consider this..how many members can recall a 'classic' advertisment from the 50's- 60's (?) for "Coppertone' Suntan Lotion' ? If I recall, it  was  a young female child, her puppy and the bottom of her bathing costume. NO WAY would that classic be acceptable today..but it was perfectly harmless and well done.