That is not completely true.If you contain some evidence but wish not to disclose it and which might help the scammer run away then it shows your selfishness.I don't think it took you more than an hour to dig the pm's and post his dox.
However, what you did should be appreciated or thanked at least but you are exaggerating a lot.
I think what he complaints about is that he was pushed to post the doxx publicly, which at the end did not serve much effect since he gave the doxx to the victims before already.
I know from experience that having a way to push an issuer or something is worth a lot. People fearing to lose their anonymity is a great push worth for scammers to pay back most of the time.
If you give that away without a real purpose or effect, remember the victims already had the doxx, then you lose alot of power.