Update 11/13/21: According to VFTW the card will be back in early 2022.
Around the time that American Airlines announced changes to elite status, including the introduction of Loyalty Points the Barclays American Airlines business card stopped accepting new applications. At the time I thought this would be temporary and new benefits would be added to the card to reflect the new Loyalty Points, but the card has not returned and customer service representatives are now stating the card has been discontinued. Because of this we have removed this card form our best credit card bonuses.
Source: doctorofcredit.com