Encoding purpose is as easy as creating artificial needs in agents. But sure, if "«self-motivated actors»" wanted to signify "creating an axiology", as part of the ontology, that is surely a (qualitatively) significative piece.

But if I wanted to deal with sentient beings with a world model, cats are already available and there is little need for artificial ones.

When we develop artificial intelligences, that is to have reliable problem solvers. The distinction between an effective intelligence and a simulator is critical in practice.