You can’t take things out of context. There’s currently a far right US presidents creating an economical war with the historical allies and economical partners of his country. The point of boycotting is to try to prove him wrong about thinking that he can impose his wishes by force, the target is him and his government, not the US people in general. There’s also the hope that weakening him could allow a political change next term, which would make things better for our American friends. Of course it is political, but it’s against Trump, not the people.