The definition of a ML Engineer varies from company to company. For some, it is the way you describe it: the data scientist builds the model, the machine learning engineer industrialize. But in a lot of other companies like mine, the ML Engineer builds the model from scratch and is responsible for the end-2-end ML project. In my company there are no data scientist. There are data analysts, ml engineers and data engineers. It is way more fun like that. I would hate to be given a model with the requirement to industrialize it without being the genitor of the said model