I mainly use Qovery because it allows me not to handle the deployment and the maintenance of our infrastructure. Also, Qovery makes the eventual switch from GCP to AWS or any other cloud service really easy without any setup from our side. It perfectly integrates with the containers we use in our dev environment. I don't see any reason not to use Qovery.
I would recommend Qovery for any teams for which DevOps is not part of the business (yet) and for bigger teams who want to prototype fast or delegate some functionality to the developers directly. Managing test environments without defocusing DevOps is really handy.