I know plenty of folks are still angry, and felt anything short of "W00t! 2A Beyotches! NFA '34 and GCA '68 repealz!" is a slap.
And there's some rather hurtful things "on our side" Scalia put in the decision in regards to what regulations were permissible, and wobbly on the scrutiny standard as well.
However, an even further sweeping decision in RKBA's favor would just be a juicy target for the anti-Left to go after. And judicial restraint on the part of the court isn't just for the sake of judicial restraint as a legal philosiphy. See-saw ideological swings and decision reversals can severely undermine the separation/balance of powers in the fed.gov.
And getting the ultimate "big win", it also puts RKBA's eggs, court-wise, all in one basket. I'm no moderate on RKBA, however, I would rather see us gain ground
consistently, even if it takes inordinately long, than keep betting on the legal version of Hail-Mary end-zone passes. IMO, "It was the right thing to do" is small comfort when you
lose.
Anyone who thought post-Heller decisions like Chicago vs. McDonald wouldn't still take a lot of time and effort to enforce, essentially grinding down the municipal bureaucracies until such time that it became easier for them to comply, than resist... were dreaming.
That's not to say don't go-for-broke in places like CA where we've arguably got (almost) nothing to lose anymore, but I'm not as sanguine about gambling our (government recognition of our pre-existing natural) rights on legal bets with 50/50 odds or worse.