From the AWS website: https://aws.amazon.com/ec2/graviton/
AWS Graviton processors are custom built by Amazon Web Services using 64-bit Arm Neoverse cores to deliver the best price performance for your cloud workloads running in Amazon EC2. Amazon EC2 provides the broadest and deepest portfolio of compute instances, including many that are powered by latest-generation Intel and AMD processors. AWS Graviton processors add even more choice to help customers optimize performance and cost for their workloads.
Since most clients who are monitoring RDS and Aurora instances are using an EC2 instance, it's likely that this processor architecture will become a more popular platform for running our agents over time.