can a sagemaker endpoint be made public?

I believe the way to make a sagemaker inference endpoint public is to use api-gw infront of it. Check out this solution https://docs.aws.amazon.com/solutions/latest/constructs/aws-apigateway-sagemakerendpoint.html

Hello. In order to make an Amazon SageMaker Real-Time Endpoint public, you can create and manage APIs through an API Gateway. This is an official blog that is showing you a possible solution:

https://aws.amazon.com/blogs/machine-learning/creating-a-machine-learning-powered-rest-api-with-amazon-api-gateway-mapping-templates-and-amazon-sagemaker/