When we played Dungeons and Dragons at school, the GM controlled the adventure. Every stage was planned: our choices were irrelevant, because the GM made them fit his adventure. Sometimes, he was blatant, blocking our ideas: "You can't go south. There's a huge cliff.". Sometimes, he tricked us, making it seem like our decisions mattered, even though they didn't: "All right, you go south. You come to a big castle."
We used the rules we liked and ignored the ones we didn't. Often, we'd fudge die rolls: "Let's say you pick the lock". Sometimes, we'd fudge them less obviously: "But then you notice another way in". We'd ignore the character sheets, which would often stay in the drawer.
At the time, it seemed like fun. Looking back, though, it probably wasn't. I'd sit in my room, for hours, drawing dungeons. I'd buy all the latest books. But I wasn't really enjoying myself.
Having read stories like this, many times, I'm getting suspicious. I'm not sure they're entirely true. They're not false, either, but I think we're kidding ourselves, just a little.
Here's what I think happens. We read these stories on forums. Then we look back at their own experience and think: yes, we did fudge die rolls. Yes, we ignored rules. And, gradually, we start to see our experiences a little differently.
Then there's a period of social validation. It's socially acceptable to tell such anecdotes: if I say "Dungeons and Dragons sucks", lots of people agree. It validates our identity a little: we're indie gamers, dammit, and we've moved on! There's a political sense, too. Indie games do things differently from Dungeons and Dragons, so it's useful to point out how the old way was bad.
It's not entirely false. There's definitely elements of truth in these stories. But it's carefully constructed and selective. I think it's a myth: not false, not real, but something subtly in between.