I would say that it's a real trope, but so rare in its 'genuine' form as to make it questionable whether it really needs its own page. Many of the examples there seem to be shoehorned in — things like 'well, you could
interpret these as the four elements'.
Most 'ensemble' tropes suffer from that problem (especially Five-Man Band
, which for some reason people love
to stuff groups that don't even have five people into), and it's not as bad here as in some of the others, but the description should make it clear that only groups of exactly four people who are explicitly
each themed to an element qualify.