Assuming I'm decoding this correctly, it is not true as a matter of law. Denial of cert means nothing, except in the particular case at hand, in which it means that the lower court rulings stand. It says nothing about the merits of the case, creats no law/precident. In this case it means we have no individual RKBA, at least in those circuits which have ruled that way, all but the 5th IIRC, and even there it's a weak right that can be abridged on a "reasonable" basis.
As a mater of practical politics, it means the gun grabbers will be emboldened and we can expect a sh*^storm of new gun ban/control legislation, at both the state and federal levels.