On a literal level: pretty much any supernatural story involving a werewolf.
On a metaphorical level: pick your favorite male-focused self help pop psychologist. There's a reason the phrase "sigma male grindset" was coined to make fun of these people.
Are you seriously going to claim that "few to no people believe in or care about "alpha wolves"" given the enormous representation of the concept in the last fifty years of western literature?
I honestly have never seen "the enormous representation of the concept ["alpha wolf"] in the last fifty years of western literature", yes. In fact, I don't see much representation of wolves in the western literature, let alone particular types of wolves. Even such exciting creatures as werewolves seem to be far less popular than vampires.
Google Ngram Viewer shows some initial interest starting around 1965, plateauing until '74, relatively low until '87, and rising pretty steadily from there (with a small dip in growth around '03, and a meteoric rise since then). This seems to support the argument of it being common in western literature of the last 50 years.
Ok, so according to Google Ngram Viewer there is a bunch of widely unknown romantic novels about werewolves that mention alpha werewolves. And according to TV Tropes there is fanfiction that constructs elaborate hierarchies with all sorts of castes including Psi and Chi. That's hardly "the enormous representation." Well, at least now kids who learn biology by reading Omegaverse fiction can unlearn horrible misrepresentations they were led to believe in!
On a metaphorical level: pick your favorite male-focused self help pop psychologist. There's a reason the phrase "sigma male grindset" was coined to make fun of these people.