Simple Queue Service - SQS is a fully managed message queuing service that makes it easy to decouple and scale microservices, distributed systems, and server-less applications. Amazon SQS offers common constructs such as dead-letter queues and cost allocation tags. It provides a generic web services API that you can access using any programming language that the AWS SDK supports.
Server-side encryption (SSE) lets you transmit sensitive data in encrypted queues. SSE protects the contents of messages in queues using keys managed in AWS Key Management Service (AWS KMS).
When you are using AWS SQS queues to send and receive messages that contain sensitive data, it is highly recommended to implement encryption in order to make the contents of these messages unavailable to unauthorized or anonymous users. The encryption and decryption is handled transparently by SQS SSE and do not require any additional action from you or your application.
By default, SQS queues have Server Side Encryption disable.
If you want to revoke the change then follow the implantation steps and choose Disable at step 4 and click on save.