I have a slightly different take on this. It does not really matter what we do to the world. Action actually has two other purposes, which sometimes we miss altogether.
The first purpose is to hold up in front of our faces what is the mechanism of our mind, our decision points, our value systems. Since most of our actions are reactions, they reflect quite accurately our inner workings, provided we are humble enough to look inside and see them without defensiveness. This needs awareness of course. We should be able to look at our action and ask: Now what made me act like that?
Having done this, we need to recognise the second purpose of action, that is to modify or improve our inner working to make it more refined, benevolent, driven by good values and less compulsive. We do this through the deliberate actions of introspection, meditation, selfless charity and worship.
These two are the main purposes of action. What we really do to the world outside is relatively unimportant. As our mind becomes more evolved, our need for action itself reduces. Sages who do "nothing" have probably crossed the need for action. On the other hand, an unrefined mind cannot afford to be sitting without action, because then it would have stopped looking at the mirror and halted its own evolution.
We all need to be in action, for our own sake. What benefit we do to the world is incidental.