I'm not the person you asked, but my guess is for the entertainment, but also because it's something fucked up that has real-world implications. To me, it's like watching a slow train wreck. It's just as horrible but endlessly fascinating and a tiny bit cray cray.

I also want to point out that US politics tends to dominate in foreign news outlets, so it probably gathers a bigger audience than one would expect from inside the States. Trump may say the US has no exports, but it's clear their biggest export is infotainment.