Infrastructure as code is indispensable for modern application development. You can easily update resources in a CloudFormation stack. The core issue you point out is with the abstraction layer that the Serverless Framework provides. I never got into using it because it is better to understand how to do it yourself. If you master CloudFormation (and now CDK) you will never need another framework like Serverless Framework.

Ex Amazon Engineer and Founder of @AdonousTech. A technology company focused on #VoiceFirst #Serverless and #Cloud applications for small businesses