Apple brandy and applejack are distilled from apple cider. Applejack is usually made with freeze distillation, which is perfectly safe. Simple alembic distillation is safer than some things you might already do in the kitchen, like pressure cooking.
“Perfectly safe” eh… freeze distillation doesn’t remove methanol so it is far from perfectly safe, but closer to “probably be fine” than poorly handled alembic would be. I think people should have the right to make their own alcohol if they want, but I’m probably not rushing to drink other people’s distilled trashcan mash.