The purpose of meditation is to improve your life. When your life is well and fully improved, then you can think about the purposelessness of meditation. Meditation becomes purposeless when you notice that your life cannot be improved, not because it is hopeless, but because it is perfect. Imagining that your life is perfect is not quite the same as noticing it. If you feel like your life could and should be improved and you console yourself with the idea that you are likely perfect despite the evidence, then you will continue to gather evidence to shoot holes in your perfect theory. If you happen to be doing dishes or raking the yard and it hits you that everything is absolutely as it is, as it has been and as it will be, and you are somehow okay with that, then you will not give another thought to improving your life. Until that time, it is reasonable to meditate with a purpose.
In real life it is impossible to mediate without a purpose. Nobody accidentally finds themselves in a zendo staring at a wall, enduring leg cramps and brain farts. That is done on purpose. People don’t miraculously get up an hour early every day and set aside 20 minutes every evening to sit quietly and count their breaths. That is a purposeful discipline. Once you are sitting, purpose begins to dissolve. You can’t will yourself to see the Light. You can only see what you will, hear what you do and think what you may. On many occasions you may think that meditation is a waste of time or purposeless. On many other occasions you may think that your life has improved.
Actually, people do meditate every morning and evening with miraculous discipline. When it happens that Nobody accidentally finds Themselves in meditation, it can be quite liberating for you.