yes, that is doing it for good, the morally compromised part is that the DMCA is a solution created to allow big content owners to shut down whoever they want without any culpability.
Most often things are morally neutral, and can be used for good or bad, some things are morally bad and it is difficult to use them for morally good things, and some things are morally good and it is difficult to use for morally bad. But most things are morally neutral. I think the DMCA is morally bad, but here he can use it for a moral good. But even when you use a morally bad thing for good it is still slightly bad, as in people could point at his usage here (if he chose to use it) and say "see the DMCA isn't bad" and the benefit for the bad solution his good usage promotes would taint his good usage ever so slightly.
As I tend to be more of a pragmatist I would say use the DMCA takedown if possible, but I can understand someone else feeling that would be bad.
