> Now you also need to figure out how to convert said XML into actual API calls that create/update/delete corresponding resources
Under the hood it could use cdk/cdktf/cdk8s and those frameworks would handle the rest.
> The question you need to ask yourself is why/how is this better than what Terrafrom provide
When defining resource component in a Subnet component let's say, it would get subnet automatically from current context (all parents) so developer wouldn't have to provide it directly to. Same with region, az etc. So developer don't have to track variables, but just look at the hierarchy. I think it would be more natural to define infra this way. I am not devops expert by any means, just an idea :)