Dual purpose breeds for both egg laying and meat production are poorly optimized at either. So the industry has moved onto specialized breeds that are best at doing one of them.

Plus raising roosters together is much more logistically challenging than raising hens. So they’d need much more space and much more oversight/labor. So rather than devote some resources to raising males of breeds that are good for laying eggs, they’d rather devote those same resources to raising much more meat from females of meat breeds.