I have been asked by support to post this to show that this isnt just an issue for us as a retailer - payment links cannot be paid with Amex, and there is no error screen or message when customers do attempt to pay so they THINK they have paid!
We have been having around 10% of our payment link transactions becoming a poor customer experience and time consuming as customers are assuming that Amex can be taken. The card images are small, and in this modern online world, Amex is not so rare, and Stripe who provides Shopifys payments - so the 3rd most common payment gateway - accepts Amex, as does Amazon. We are a wintersports retailer so we have a lot of customers with Amex trying to get Airmiles so have had to accept it in store.
Please can you accelarate the new payment solution that will allow you to offer Amex, according to support. There is not enough room on the payment link text field for us to be manually putting a warning in every time we send a payment link, and we shouldnt need to - the UX is so poor on this, as there is no warning or error screen when you try to pay by Amex :(