Those disavowals were necessary because Clinton has made gun control a centerpiece of her presidential campaign, contrary to the conventional wisdom about the political risks that entails. But Clinton's assurances ring hollow, since it's pretty clear she not only does not value the individual right to keep and bear arms but does not believe it is guaranteed by the Constitution.
After Democrats' losses in the 1994 congressional elections and the 2000 presidential contest were widely blamed on their support for gun control, the party changed its platform. In 2004 Democrats promised to "protect Americans' Second Amendment right to own firearms," while the 2008 and 2012 platforms both included this sentence: "We recognize that the individual right to bear arms is an important part of the American tradition, and we will preserve Americans' Second Amendment right to own and use firearms."
This year Democrats erased the Second Amendment from their platform, reverting to the approach they took in 2000 and earlier. The 2016 platform mentions "the rights of responsible gun owners" but says nothing about the extent of those rights or the legal basis for them.
The Second Amendment's excision from the Democratic platform is consistent with Clinton's opinion that District of Columbia v. Heller, the 2008 case in which the Supreme Court recognized that the Second Amendment protects an individual right to armed self-defense, was "wrongly decided." At the very least, that position means Clinton thinks the Second Amendment does not guarantee the right to use guns for self-defense in the home, since the law overturned in Heller made it impossible to exercise that right.