I don't understand how you correlate difficulty with a game's ability to transcend the genre or excel. The game that immediately springs to mind when I think of gaming carrying over from "beyond the play period" is The Last of Us. It's not my all time favourite game, but after I was done with it I could take a step back and say "that is an example of what games can accomplish at their best." It has the emotion and storytelling of a great book or film, coupled with the long, "your struggle is my struggle" investment that games provide better than any medium. Those things combined make that game what it is and changing the difficulty setting doesn't diminish either one. Some people simply prefer to get through the game without breaking a sweat and others want an extremely challenging experience. This is another reason why gaming is a potentially superior medium; it allows itself to be catered to a wide ranging audience.
Chances are that a lot of people also have a different viewpoint to me on what constitutes an influential experience from a game. That guy who played Dark Souls with a guitar hero controller probably had a similar feeling of unforgettable accomplishment as the grown adult who beat The Last of Us on easy, and both are equally valid and can't be diminished by other people.
Games are meant to be fun. Mindless fun, thought provoking fun, stressful, relaxing, emotional, shared, all of those and more depending on the game played and who played it. What I find stressful other people may find easy, and what I find emotional other people may find boring. It's not up to any one person to dictate how a game should be received by everyone (not even the developer), which I feel like is the ground you've been treading very close to. Honestly, who cares if people cheat their way through a game? You enjoyed it, if they didn't and you feel they could have then simply feel sorry for them and move on.
Also, in regards to ffnut's point about asking for help and being told to lower the difficulty; it takes less than one second to ignore bad advice. The internet is full of it and it's probably not worth giving everything you read on it credence.