Pulumi allows credentials (KUBECONFIG, AWS_ACCESS_KEY_ID, etc) to be overridden by environment variables. From
https://www.pulumi.com/docs/intro/cloud-providers/aws/setup/#environment-variables,
"Although credentials are recommended, the SDK will prefer environment variables over any other settings". If you unset your AWS environment variables I would expect Pulumi to use the configured settings as described on the setup page.