Agreed about that. I was hired onto a team that inherited a large AWS Lambda backend and the opacity of the underlying platform (which is the value proposition of serverless!) has made it very painful when the going gets tough and you find bugs in your system down close to that layer (in our case, intermittent socket hangups trying to connect to the secrets extension). And since your local testing rig looks almost nothing like the deployed environment...
I have some toy stuff at home running on Google Cloud Functions and it works fine (and scale-to-zero is pretty handy for hiding in the free tier). But I struggle to imagine a scenario in a professional setting where I wouldn't prefer to just put an HTTP server/queue consumer in a container on ECS.