I'm not saying all of them do. But I'm pretty sure most of them do.
Remember, I'm actually speaking from experience and you're speaking more from opinion.
I know what my peers are like, and I know that there are plenty of teenagers who went to see RotS who aren't even fans of Star Wars. If you asked them who Bossk was, they wouldn't know. And if you explained that he was one of the Bounty Hunters hired by Darth Vader, I doubt they'd know what you were talking about. If you were to ask them what species Jar Jar was, most of them wouldn't know.
my point is, there is a difference between the people that the PT appeals to more, and the people who are actually Star Wars fans. My cousin who is 5 likes watching TPM, to him, it's just a movie like Toy Story or The Lion King, and he thinks ANH is boring. This may change as he gets older, but right now, the PT appeals to him. But he's not really a fan, he's just one of the billions of people who watches Star Wars. I'm not a fan of Titanic. I think it's boring. But it was such a big movie, that I saw it. I actually saw it a few times, through friends and family. But that doesn't mean I liked it... Do you get what I'm trying to say? I would understand if you said (or Lucas said) the PT appealed to people under the age of 25 more, because that would make sense. But saying that FANS under the age of 25 prefer the PT more isn't really true.
Er... I'm not trying to argue with you, and I didn't mean to write such a long reply, and I doubt I'll change your mind about anything you've already said. That's just my 2 cents. I can't even remember what I wrote anymore...