The most professionally competent people don't see the world in terms of "what I can do vs. what I can't," but more "how can I get paid more for my capabilities than I currently am."
That might involve doing more work, but at some point, everybody who makes too much gets lazy while still making too much.
His experience is just making him look for an approach that will allow him to consolidate activities while gradually getting raises. If you don't understand the world in this way, then maybe you should take those responsibilities, because worst-case scenario is that you now have more experience that you can put on future resumes.
Once you wake up, you'll see the advantage.