OA will be fine but the definition of success will change. It makes sense that listings and brands were restricted. The corners cut by some Amazon Sellers poses reputational risk to the brands and Amazon itself. At some point, the hassle isn't worth the extra income for them. Could Amazon have picked a better time than Q4? Yes. Did some high integrity folks get caught in the middle? Yes. I expect there will be changes in the OA community over the next few months. Many will quit, others will be more profitable than ever.