First of all, this is stupid. Immortal cultivation run on some sort of energy from world. So, you are dead if you are in a void where there is no energy for you to stop. In that regard, martial arts are more reliable that they are breaking your limits not borrowing strength from the world to work around limits. Second, by cultivating, you are absorbing energy of the world, meaning, you are giving yourself to the world for longevity. So, you are just a glorified slave of the world. Sure, in your world, you will be pretty strong but what if you are in another world? You would just be some ordinary guy. Third, you are limiting yourself. You can only advance when heaven allow you to whereas martial artists can break through with enough hard work.
