Unless I misread the article, but the writer makes a claim of having to support 100 req/sec with about 50 instances. "For Fargate, this meant deploying 50 instances of my container with pretty beefy settings — 8 GB of memory and 4 full CPU units per container instance.". If the api service was just returning some data with a few manupilations, then that is quite inefficient. At NodeChef ( https://www.nodechef.com ), there are users running over 1000 req/sec with just around 12 containers each with 512 MB ram and 2 CPUs.
Another alternative to deploy a Rails and PostgreSQL app is on NodeChef where developers have three simple options to choose from to deploy apps. https://www.nodechef.com/
If you want to look at it from popularity angle, we continue to see many meteor deployments on https://nodechef.com/meteorhosting suggesting it's still a popular choice out there.
NodeChef provides a great platform for developers who don't want to wrangle with the complexities of server-side infrastructure or using multiple services to host an app. By Integrating both the database and the app server into a single cloud service, developers are able to effortlessly host their applications.
There is also NodeChef object storage. NodeChef charges only by the storage size of your instance. No Data transfer charges. No additional charges for PUT, GET, COPY, or other operations. https://www.nodechef.com/s3-compatible-object-storage