I checked on the Am-Ex issue and found that ebay besides increasing final seller fees and charging fee also on shipping has now blocked some categories like jewelry, coins, etc from Am-Ex because they don't want to pay extra half% to card company.
But for some reason, if you were in shina ebay would not block it.
If buyer ask ebay cust serv, they blame the seller.
If seller ask ebay cust serv, they blame the buyer.
I attached a photo from ebay community forum