Trump had something lie 310 stories about him, and the next highest spotlight guy was Jeb with 180 or something like that. It's about media coverage. You might not win by that, but Hillary has been in the press for 30 years or so. Sure people knew who Trump was but he's portrayed himself as an arrogant asshole for ratings on TV. He probably is an arrogant asshole. Regardless, you cannot get the toothpaste back into the tube.
It's going to be hard to have any real candidates for the next 20 years. I don't see any on the horizon unless the Speaker of the House becomes popular. I'd bet on Chelsea or Mic e Obama before that. Bush, his son, his other son, Clinton, his wife, and you watch, Hillary will appoint Mic e with a post.