BBC makes switch to AWS, serverless for new website architecture, but observers note HTML unclear?

Source:

https://www.theregister.com/2020/11/04/bbc_embraces_aws_serverless/

"What is the cost impact of moving from on-premises to AWS? 

What is the cost impact of Lambda versus using EC2? 

Why, if the caching and content delivery network is working as expected, are 2,000 lamdbas a second required?"