This isn't true. 10GB is the limit on docker backed lambda function sizes. Layers are capped to 256MB just like lambda functions.
A couple of weeks ago, I tried to deploy a lambda function that created Azure Subnets in python, and the Azure client was 265GB alone. My layer creation api call failed because of this.
https://aws.amazon.com/blogs/aws/new-for-aws-lambda-containe...