Non-Americans is of course a massive generalization that can have no one answer, and has many different answers which vary in various ways.
Things I have heard from non-Americans about Americans include:
wonderful
kind-hearted
friendly
free
sexually liberated
allowed to be who they are
open
well-intended
naïve
innocent
money-oriented
work-ethic-obsessed
easily-identified
backward
a very strange country
crazy
insane
xenophobic
self-centered
entitled
uncultured
uneducated
ignorant
poorly dressed
loud
ill-mannered / rude
obnoxious
uncultured
xenophobic
politically:
the people are mostly good and different from the politicians
OMG Gary Hart was disqualified to run for president because the media reported he had ONE mistress!?!?!
OMG why do you not have affordable healthcare?
OMG why did you elect a retarded fascist criminal POTUS (heard for Reagan, GW Bush, and especially Trump)
I have also been told “you don’t seem like an American” a lot, which I usually take as a compliment.