Under the terms of this Board's Policy document, if you disagree with a description of an item offered for sale on eBay or in any other online marketplace, this is how you should handle the matter in respect of posting on the board:
If you wish to draw attention to an on-line auction which you consider to be "not as described" you may provide a link to the auction but you should only state that "in my opinion this piece has not been described correctly." Or, for example, in the case of a signature that you feel is incorrect "the signature does not appear to be genuine." It would also be advisable to ask if others have any opinion. Do not state anything is a fact, unless you can provide documentary proof!
If you wish to have an in depth discussion about the rights and wrongs of eBay or other marketplace policies, please use the forums of those marketplaces to flag up the issues with the owners of those marketplaces, instead of this board where we have no influence on other sites' policies and practices. Many thanks.