There are certainly many fakes listed, as scammers are constantly listing them, and even when a listing is removed that does not stop the scammer from trying to list again from other accounts. The same sorts of scam items do tend to get listed over and over again from different accounts.
But it does not necessarily follow that just because there are many scam items listed that the majority of actual sales are sales of scam items.
Buyers can avoid many scams by choosing to only deal with experienced sellers, particularly when buying items that are known to be frequently counterfeited, and by avoiding deals that are obviously too good to be true. A seller that has been selling on eBay for a long time and that has a track record of receiving positive feedback for selling and actually delivering coins or similar items is much less likely to turn out to be a scammer, or to sell a counterfeit item.
Accounts that are new or that have no history of selling similar items are comparatively much more likely to be the source of counterfeit items, or else to be found to be flipping items that turn out to be counterfeit.
