Does this run a separate Beam instance for every Function? If so, isnt that an enormous waste of Erlang? If not, how isolated are requests? Can I send messages between them? Should I?
Given this, using beam is a bit of a waste in terms of individual instance scalability. That being said however, you might be able to use shared actor pools (e.g. caches, etc.) across all your functions. I want to emphasise the might as rapidly adding and removing nodes from the beam cluster might not work well or at all.
At the end of the day, the lambda model kind of supplants the actor model as your unit of messaging and concurrency, and so trying to mix the two isn't the best idea. If you want to use the beam on AWS I'd recommend sticking to ECS/Fargate/EKS. That being said, Elixir might be a nice match due to developer ergonomics, just don't expect to be able to drag and drop actor reliant features.
At re:invent this year, someone on the Lambda team indicated that they were working on something in this space, but couldn't say exactly what, or give any real timeline.