Quite frankly, in comparison to 3/4 of the world, Americans don't have a whole lot to complain about, but I think they complain more than everyone else.
That's because in 3/4 or the world, you can't complain without repercussions - even death in some places. And one doesn't have to '(leave) the country much' to know that. Even GB doesn't have the freedom of speech and press that we have here.
But.... comparing the rest of the world vs. the US isn't the best comparison - it's
now in the US vs.
what it was before the regulatory state the US has become, and
before political correctness became a 'standard' in media and in life. (
like most of the other countries to which you refer, btw)
And
That's something to complain about, because both have been an unwelcome intrusion into the lives of individuals who just want to live their own lives, rather than being told by others who 'know what's best' for us and are willing to use force to make us comply.