"The Royal Family" gets similar treatment. I suspect that it's a language thing---there are only two Anglosphere countries with presidents, and the other one (Ireland) has ~1/50th the population of the US and lots of Irish speakers, so if you see an English language post about "the President", then there's a good chance that it's referring to the US one. I'd like to see speakers of other languages (or Anglophones from outside the Anglosphere) confirm or refute this hunch.
In Germany elections don't rely that heavily on the candidates so it is hard to say. But generally speaking there is no clear identification as well, (except for the fact that the address ends on ".de")
