How is this a victory? The Court has ruled that even though there is a Second Amendment right to keep and bear arms, such right only applies insofar as the government can't claim its restrictions are "reasonable", and such rights may be forfeited without any substantive due process.
It's a victory because finally there's language recognizing the 2nd as an individual right, like many of us have believed (correctly) all along. Up until now, the 2nd was seen legally as something of a collective right.It remains to be seen what constitutes a "reasonable" government restriction on one's 2nd Amendment rights, but such muddiness in the face of absolute language isn't necessarily to be feared. The "Congress shall make no law" aspect of the 1st is, when dealing with speech, routinely read to permit prosecution for libel, for example.