While I kind of agree with the sentiment, there are two important ways I disagree.
First of all, I agree with Henry David Thoreau who said it wasn’t his job to fix the world, he only wanted to live in it. I think that people who forget this, who make activism their whole life (whether it’s the passive aggressive kind, or the somewhat more reasonable way deBoer advocates), are just burning themselves out and doomed to fail. Remember that the best efforts may fail. You can’t save a world that doesn’t want to be saved. So do what you feel you must, and then wash your hands of it, put it behind you, and go on living.
Second. Don’t underestimate the power of just being, as opposed to doing. Salt of the earth, being the change you wish to see in the world and all that. It may not stop, say, climate change, right away. But just being there, and not being the caricature/demon your ideological opponents paint you as, can work miracles.