I'm going to bring up LAST LAUGH (yet again). Dick and Barbara talk about the Joker. Babs feels guilty about the Joker's latest mass-murder spree because "We never did anything permanent to stop him." Babs even thinks maybe they should stand aside and let the Joker be killed (President Lex Luthor just gave the kill order.)
In this case, maybe Spider-Man thinks he doesn't have to kill Osborn in order to defeat him. Dark Reign looks to be going on until at least September. Peter could show some semblance of long-term planning in taking out Osborn so he's not in charge of everything. That would allow life to suck less for all superheroes everywhere instead of just Peter Parker.