This makes more sense than "you have to eat protein within one hour from exercising". Why? Because wouldn't it take a lot longer for the protein to get digested

This makes more sense than "you have to eat protein within one hour from exercising". Why? Because wouldn't it take a lot longer for the protein to get digested in your body? Possibly many hours, depending on the source of protein. And if, after exercising, I'm still digesting protein I've eaten several hours earlier, what difference can it make if I add some more that will just get digested several hours later, provided that the total amount of protein is kept constant.