The important thing to remember about Justice Gorsuch is that he DOESN'T represent a tide change in the SCOTUS.
Yes, if another J. Kagan, J. Sotamayor, J. Ginsberg, or J. Breyer were appointed to the bench it would have been devastating to 2nd Amendment jurisprudence (among other things), but that's only because a staunch originalist would have been replaced by a Justice who subscribed to the "Living Document" argument.
As it stands, an originalist was replaced by an originalist. The makeup of the court is more or less exactly the same as it was before the passing of J. Scalia. The same makeup that has refused to hear any substantial case regarding the 2nd Amendment since McDonald. Consider Kachalsky, Woollard, etc.
There are a lot of theories as to why SCOTUS has refused to rule further on the matter... the one I subscribe to revolves around the 3 consistently originalist/textualist justices (Scalia, Thomas, Alito) and the 4 constantly "living document" (Breyer, Sotamayor, Kagan, Ginsburg) being unsure of how the two swing votes (Roberts, Kennedy) will swing on the matter.
If the living document types were sure that either of the swings would go their way, you'd see 4 votes to grant cert and the Heller decision further reduced into irrelevancy. The originalist/textualist types don't have the numbers to force cert like that however, so they would have to first be sure that both swings would go their way, and then convince one swing to agree to cert.
There are clear indications that J. Thomas and J. Alito (as well as J. Scalia) are tired of the lower courts thumbing their collective noses at the Heller decision (See the dissent in denial of cert for Friedman and the concurring opinion in Caetano).
The only monumental change that may be coming down the pipe is the retirement of either J. Kennedy or J. Ginsburg in the next 3.5 years. To that end, it may have to happen in the next 1.5 years, depending on how the off-year election goes. Otherwise, it's a crap shoot whether the two previously mentioned justices would be replaced with an originalist or not.
