Where I work we use option [2] - It works well. All merges to the main branch auto deploy to our Testing environment. Properly formatted tags go to Production a

Where I work we use option [2] - It works well. All merges to the main branch auto deploy to our Testing environment. Properly formatted tags go to Production as a release. The front-end team get branch based deployments. The backend has their local docker development. Try as we might, creating all the infra even with 100% terraform is a challenge - mostly for the swallowing of the AWS bill. We just could not see the cost/reward for doing more than just non-prod + prod. Totally open to ideas why 2 non-prods is better than 1.