Who is Most Americans? I'm okay with any sort of sentence that begins with "Some people," because "Some people want to experiment sexually with small mammals" is probably true. But when you cross into "most" you're making a statistical assertion of majority, and that sort of thing requires fact instead of ho-hum generalization.

What happens when you say "Most Americans" in this way is the creation of a mythical Other. "I'm American, but I'm different from _those_ Americans." (I am aware that I'm assuming you're American.)