JH has a huge amount of ungroomed terrain but that is not the same as back country.
Back Country refers to skiing that is outside the confines of a resort. There is no lifts, no ski patrol and as such requires a different type of gear then resort skiing. I don't know what videos you were watching but they may or may not have been within the resort. There is a significant amount of popular backcountry around the resort. If you have little experience with ungroomed terrain then JH will be a great place to get a taste for it. Your skis will be fine.