(A followup from The Straw Stereotype)
Some people (e.g. on Quora) imagine that "Siberia is colder than Greece" means that at every second of every minute of every hour of every day from the start to the end of time, the temperature will always be lower in Siberia than in Greece.
Let us examine how English is used in the real world.
Firstly, by the New York Times:
The Anxious Americans
"AMERICANS are a pretty anxious people"
Does this mean that ALL Americans are anxious?
Americans Are Finally Eating Less
"Americans’ eating habits have begun changing for the better"
Does this mean that ALL Americans are eating better?
The Asian Advantage
"Why are Asian-Americans so successful in America?"
Does this mean that ALL Asian-Americans are successful in America?
Across the pond, the Economist is equally guilty of this:
The model minority is losing patience
"Americans are spending most of the oil-price windfall after all"
Does this mean that ALL Ameicans are spending most of the money saved from lower oil prices?
The case against tipping
"Americans are caught in a nasty cycle of low pay justifying tips and tips justifying low pay"
Do ALL Americans use low pay to justify tips and tips to justify low pay?
Those who denounce unqualified general statements should feel free to write angry letters to the Editors of both of these publications, generally considered houses of good writing, denouncing their patently false generalisations and/or their abuse of the English language.
Yet, we need not stop here. We can look at more appalling generalisations from atrocious writers:
"The English are, so far as I know, the hardest-worked people on whom the sun shines" - Letter of Charles Darwin to Charles Knight, 1854
"What a degenerate people the English are" - Letter of Ernest Hemingway to Maxwell Perkins, 1940
"The English are always degrading truths into facts" - Oscar Wilde, A Few Maxims for the Instruction of the Over-educated
"We Americans are tainted with this insanity" - Society and Solitude, Ralph Waldo Emerson
"[The British] are the only people who like to be told how bad things are, who like to be told the worst" - Speech in the House of Commons, 10 June 1941, Winston Churchill
It seems, then, that all of these so-called writers are guilty of preposterous generalisations and sweeping statements.
In reality, it is pretty obvious that this sort of mindless quibbling is a particularly pathetic form of motivated reasoning; it is easier to "rebut" someone who points out a trend or tendency you disagree with, using The Straw Stereotype ("A are B" means "All A are B") than to actually show how he is wrong.