But he did say that about immigrants. Or maybe illegal immigrants if you want to specially charitable. If he would said that about mexican gangs people would be less angry about it.
You can argue semantics of the full quote, but the only way you get to, "Trump called all Mexicans rapists" is: a) ignoring the context of the remarks being on illegal immigration, b) implying examples apply to the entire population, and c) ignoring the remainder of his remarks.
When Mexico sends its people, they’re not sending their
best. [...] They’re sending people that have lots of
problems, and they’re bringing those problems with us.
They’re bringing drugs. They’re bringing crime. They’re
rapists. And some, I assume, are good people.
If you want to argue pure semantics, you have to be concerned that Trump thinks Mexico is sending people, you should be confused about how "they" bring problems "with us", and stuck in a moral quandary about how all Mexicans in the U.S. are drug-toting criminal rapists who are also good people (maybe). You could never get to "all Mexicans" unless Mexico is "sending" 100% of its population.
Or, you interpret the remarks to mean that illegal Mexican immigrants are more likely to be drug-users, criminals, and rapists, with the immediate and explicit caveat that this charge does not imply to all illegal Mexican immigrants, because at least "some" of them are good people.
