Gyms have benefits, sure, but he's responding to someone treating it as either go to the gym or get no exercise. He's pointing out alternatives. They don't need

Gyms have benefits, sure, but he's responding to someone treating it as either go to the gym or get no exercise. He's pointing out alternatives. They don't need to be as good to be relevant. The fact that push-ups exist refutes the false dilemma. The fact that gyms exist does not refute the idea that you can stay fit without a gym.