I do think this is an important concept to explain our conception of goal-directedness, but I don't think it can be used as an argument for AI risk, because it proves too much. For example, for many people without technical expertise, the best model they have for a laptop is that it is pursuing some goal (at least, many of my relatives frequently anthropomorphize their laptops).

This definition is supposed to also explains why a mouse has agentic behavior, and I would consider it a failure of the definition if it implied that mice are dangerous. I think a system becomes more dangerous as your best model of that system as an optimizer increases in optimization power.