You're creating an issue here. It might be because once one leaves school, their lives are swamped with work and trying to survive. It gets to be hard to keep up. Most of us don't have time to spend on constant study. So the only time you get exposed to these things is via the news. You might have noticed Justin Trudeau has been in the news more because during Trump's presidency, he made a point of making bullying remarks against Trudeau. Clear case of jealousy that Trudeau is better looking and more well respected. Trump's ego couldn't handle it. So Trudeau's name became more familiar and was out there more.

Also, Trudeau has been Prime Minister longer. He's been in office, what, 7ish years? Manuel Obrador has been in office, what, 4 maybe 5 years? He's also not had anywhere near the media exposure in the US.

Trump is racist. I can't remember a single time he mentioned Obrador by name. I don't watch Faux news but I would guess he wasn't mentioned by name much there either. Much of the news has become so caustic, people have tuned out and disengaged. The average person's life is hard enough. Nobody wants to listen to a bunch of talking heads and their never ending diatribes anymore, except for those special individuals who get off on that kind of thing.

I don't think you have a legitimate case for racism unless most Americans can name the political leaders of all predominantly white nations, even the ones who are not considered first world, but not South and central American, Asian, or African ones.

Greenland is a near neighbor too. As is Cuba. Most Americans would recognize the name Castro for sure. They may not be able to recall the current president of Cuba, but would recognize the name Miguel Diáz-Canel when seen. Again, more airplay.

But how many Americans even know that the leader of Greenland is called a Premier much less that the current Premier is Múte Bourup Egede? And yes, I had to look that up. Given the fact that Greenland's glacial melting is going to have devastating consequences for the world, you'd think his/her name be more well known.