While Lambda supports containers, you lose out one one of the largest benefits of having Amazon patch/update the runtime.

Which brings me to my opinion on the value proposition. There’s a concrete cost curve where ECS/EC2 is cheaper than Lambda in what you pay AWS, there’s a much higher inflection point where you are responsible for maintenance/operations. Under that line there’s still a place for serverless.

Lamba works really well for reactive processing, such as supporting an API. You lose that benefit if you deal with something like Java because of the slow startup times gimps the processes.

Hence, running it in an environment which will be on constantly with consistent throughput that is just a pipeline 24/7. The scenario I've used it with was GIS and satellite image processing, which would have blown through the Lambda limits and with constant images being published meant that it was essentially processing 24/7.