According to Wookieepedia regarding E.U./Legends, travel to and from the Unknown Regions is hindered by a hyperspace barrier (sometimes called "the tangle").
Being that Starkiller Base is in the Unknown Regions according to The Force Awakens Visual Dictionary and both the Millennium Falcon and Poe Dameron's Resistance squadron are able to successfully navigate it, does this hyperspace barrier still exist in the new canon?
If not, is there a reason given as to why the Unknown Regions haven't been explored yet?