mmmh, I feel we misunderstand a bit the use cases here. I often faced the need in my experience to have a more dynamic way to create/delete DAGS, and I'm not talking about doing everything in YAML. And I've never written any workflows without code and git ofc :P
For instance, you have an event A, and based on this one, you create a workflow that you have templated somewhere through code. You have several options to develop the solution with Airflow, but no simple API endpoint that would enable you to do that.
Another use case is for deletion. When you have more than 2000+ DAGS, and you need an easy way to clean up some of them based on usage/naming convention, it's again a struggle due to the API limitation.
I would be happy to look at the projects you mention regarding DAG creation API, I'm not aware of these ones :-)