I have a very simple test that I apply to all generalized statements such as “all black people are X” or “all gays are Y” or whatever: replace the noun with the noun Jews. As in “all Jews are X.” We’re sensitized to this because of the Holocaust, and do it’s a useful exercise. When we’re talking about certain people, as in “George was a total shit because he did X and Y” that’s perfectly valid and a description of a given situation. When we say “all ***** are X and Y” we’re making untenable generalizations that are usually the consequences of bias. I think if more people applied this general rule we’d see a lot less nonsense from all quarters, because we all from time to time fall prey to the lure of easy generalizations. When we deal with individuals, and individual injustice, it’s easier to be both more concrete (especially when it comes to fixing problems) and more difficult to be simply reflexively blaming some generic group. It also forces the actual perpetrators into the daylight, of course.