I mean, your argument is "we can't ever be perfect so we should never even aspire to be good", which is sortof putting the cart before the horse. That we can even recognize the distinction of not being special already places in a position where we can try and do a little better. What is better, how much, or how? What even is good or morality? All of those questions are at necessity to even define good, let alone become it. Before even glancing at perfect. Sure it might be an eternal inane treadmill, but just as fish have gills to breathe, we by chance of fate have the organs necessary to think. And that's just as much in our nature. The fish doesn't consider how long it has to swim, it just does it towards a target it can see/sense. By the same mechanism that means we aren't special, why shouldn't, why wouldn't, we do the same thing? Just because what we can see/sense may be artificial, imagined, or drempt?