Because they all belong to the same semantic domain I guess.

They all come from that incel grifter nonsense. You can also throw "femnoids" and that junk in there, but the alpha, beta, and sigma stuff are more mainstream.

They originally come from that nonsense about wolves forming into packs where the alpha males get the girls and the beta males get cucked, but then they had to create a new, better category of males to keep the grift going, so the "Sigma male" became a thing. And then that spawned the "sigma grindset" idea of working yourself to death because that's how you get rich and sexy, and so on.

The teacher doesn't like greek