It has to do with fast twitch vs slow twitch muscle fibers.

Chickens are sprinters in the flight sense. They can only get themselves up in the air and back down. That's fast twitch and it's white meat.

Cows are slow AF. That's slow twitch and it's red meat.

Duck are migratory birds (i.e. flying marathons) so their have slow twitch and it's red meat.

Humans are about 2/3rds slow twitch and 1/3rd fast twitch.