The quote is from: Better API Design with OpenAPI (Cloud Next '18) on YouTube
I admit the quote is only indirectly related to proxy design in Apigee but directly applicable none the less.
Are there any plans to offer YAML or other formats/languages as an option over XML for the proxy design? Good role-models could be IaC solutions like Terraform or CDK in my opinion.
My impression is that the XML based description is not adding any value what so ever and the decision for its choice was born out of IT methodologies which have died years ago.
Editing those XML files is a cumbersome nuisance (also again I don't see any XML-specific feature adding value to the process of designing Apigee proxies) and is holding back adoption of and passion for Apigee as a product. It's not like Apigee is leveraging any XML feature beyond the key/value aspect of it and specifying scopes with tags.