Never said otherwise. Majestic got punked by a reality-warper's idea of Superman. I'd expect the same with most 14-year-old Superman fans if they had the power to do so.
We're from the internet, and frequent fan boards. Neither of our personal opinions count for much. I'm talking about sales, notoriety, etc. My mom knows Thor. Knew him before the movies, and not just because her son's a nerd. My nephew is the next generation comics will be pandering to. He's 5. He already has a plastic Mjolnir. Point is, I doubt I'd be surprised at all.
Superman is a symbol, he's a character. What he actually stands for is about so much more than just his power set. Is he really just a buff boyscout to you? I understand what you're saying, but it wouldn't undermine anything to have someone beat him, or even be stronger than him. He has been beaten before, plenty of times. It's rare, especially in strength, but if that's what you care about with him, you're missing the point.
Superman losing to He-Man wouldn't undermine the character, imo. Superman's shtick is that he's the strong/powerful guy of his company, so if it's a test of strength, then He-Man probably shouldn't win (a stalemate would be fine though). With some element of magic involved, it would probably be more easily excused. Or even have them fight more than once, and have each one pull wins from the other to even it up.
And anyone who seriously thinks I downplay Superman is going to get a rude awakening if they read the submissions I'm making to the writing tournament when they're put up.
Given He-Man's power source I don't think him being able to match or beat Superman should be scene as a negative. He's like PC Captain Marvel sans flight, but with a bad ass pet Sabre-tooth Tiger-Dragon and magic sword.