I guess it makes a lot of sense for a bot that predicts the most likely response to generate generic fantasy worlds. I think a bot DM would work a lot better if it had access to tables of tropes, environments, monsters and order elements and could roll or pick from those to create the story.

In the same way combat should probably be handled by code specifically written for that purpose similar to video games. If such a robot DM would be developed like that it would probably do much better.