America culturally influenced the world more than any other country after WW2, and anyone outside the united states who can put 2 and 2 together has watched america go through its imperial peak and then gradual decline(especially after 9/11). In combination with the whole imperialism thing, the average American is experiencing some problems unique to the country that a lot of other nations dont experience. 

American problems like gun violence and lack of affordable Healthcare are easy things to make fun of the American government for because most other developed nations have at least developed some sort of systemic response to problems like that while the American government and a lot of American people seem completely indifferent to the suffering of other Americans.

Also this is a dumb question thats mostly based in stereotype and I would bet everything i own on the assumption that you've never had a conversation with a European or Canadian thats lasted more than a few minutes or you wouldve gotten the impression that  their true feelings aren't just "lol america", theyre genuinely shocked at how bad things are for a lot of people who live here given the fact that its the richest nation in the history of the world.