Kamali's physique didn't get "ruined" by chad.
Kamali was a sub par genetics bodybuilder who managed to jag his way up to the pro ranks. He wanted to piss with the luckier big boys and it didn't work out for him because he wasn't built for that and very few are. Unless Chad forced him to try to get larger, I don't see how he got ruined by him
He clearly had issues with his arms in particular and that definitely caught up with him. Look at him now - he basically has non existent arms.
Not taking anything away from his achievement of getting into the pros, just - I don't think he was blessed, genetically. I don't think anybody could have kept him in that game.