The bit about not forcing an opening is a really good point!! Some people get so wrapped up in the "FIRST PAGE MUST GET PEOPLE'S ATTENTION" idea that they force a scene that they think might be attention-grabbing to other people into the beginning of their story, even if it's sort of out of place. I've seen people who have a story that isn't action-packed trying desperately to somehow open on action anyhow, and I'm not sure that's a good idea.
And I think the real reason to avoid a "cliche" opening is only to avoid doing it out of habit -- like, the idea that you've seen it so many times you might just default to opening the story that way without thinking about what the best opening would actually be. That doesn't mean "avoid cliche beginnings at all costs," just, "think about whether it's good for your story before you use it."