America's soft power has always been a central pillar to her hegemony and her ability to spread liberal values (actual democratic liberal values, not this weird Borg shit that's infected the West lately, mostly in North America). Her soft power, in large part, depends on her having aspirational, humanistic and somewhat universal values (to the extent that western values can be universal) so that they can be at least somewhat accessible across cultural divides - thus helping to erode ingrained cultural resistance to liberalism and, in theory, slowly making the world a slightly better place, an inch of influence at a time.
The majority of the world's population looks at shit like this, and thinks you've gone out of your damned minds. We look at the gender propaganda pushed in Afghanistan, and we get a little nervous about how you think because of how much power you have to project and push what you think. That has the dual effect of making us lose faith in your ability to manage anything (much less the defense and leadership of the "free" world) and making us look to more seemingly sane world powers for guidance and allegiance - most of those would be openly authoritarian, obviously.
This is just one insane congresswoman, but she's only one example. All of the examples, taken in isolation, seem insignificant. But taken together, they paint the picture of a nation abandoning reason (a founding pillar of post-enlightenment thinking), railing against reality, and slowly shitting itself to death.
That matters. Especially when we're talking about the world's most powerful nation and the guarantor of maritime trade.
To answer your question, the world would be a much better place if Americans gave a shit.
