You are right! I like Django admin panel, without coding you get UI and I'm comfortable with Django + DRF.
In Flask you need to add many things to make it usable.
If you check the code of the tutorial you will see that it differs from the most of the ML-to-REST-API tutorials. It's not only setting the endpoint. You can have many algorithms with many versions and stages (testing, production). There is A/B testing example. Of course you can do all in Flask but I prefer Django because many things are there already.
In Flask you need to add many things to make it usable.
If you check the code of the tutorial you will see that it differs from the most of the ML-to-REST-API tutorials. It's not only setting the endpoint. You can have many algorithms with many versions and stages (testing, production). There is A/B testing example. Of course you can do all in Flask but I prefer Django because many things are there already.