As per the definition, stereotypes are "conventional, formulaic, and oversimplified." This can be useful in some circumstances, but each of those words carries a lot of obvious negative aspects. A stereotype sometimes captures a trend within a group, but many of us commit the fallacy of applying that trend or average to every individual, forgetting about individual variation. The "sweeping judgments on whole peoples" to me describe trends. Fair enough, but again we confuse trends and data points. For me, the solution is to use careful language. To say "American women are X" is shorthand that results in stereotyping. To talk about cultural trends within a group is a safer approach. Of course some people won't pick up on this distinction and will continue to think in stereotypes.

It's basic science education, which is weak in many places in the world. In science, it's called the ecological fallacy, though it's not restricted to ecology:

Ecological fallacy - Wikipedia, the free encyclopedia