Every bird you ever raised reached 8 weeks = fryer age . Nothing to do with breed really . Back in the day my Great grandmother was in charge of the setting hens . She kept a steady supply of chicken for the table . No freezers or electric . Dual purpose breeds were the staple on most farms . Eggs , enough size for eating and broody for a steady supply of fried chicken . It took skill to have chicks hatch every 2 weeks or so . Small batches just enough for the family . If the family was large it took more chicken .Yep....I own my neophyte status! I actually don't have any fryers. Most of my birds are dual purpose (Orpingtons, Australorps, Ameraucanas, Cream Legbar, etc...). Some are smaller/skinnier birds (Starlight Green, Prairie Bluebells, Gamehens, Blue Andalusians, etc...). And of, course, I have barnyard mixes...although all my roosters are pretty big boys. I culled a roo last fall that was the size of a small turkey...no joke.
So none of my birds are fryers although I am very tempted to get some....ha ha. And I wouldn't say we NEVER get a tender bird.... We have had a couple which were very tender and succulent. DH usually grills them. Sometimes he can overcook them which, naturally, makes them like hardtack almost. But I'd say 60-75% of the time, they seem tougher than I'd like.