"The only way we can improve our circumstances is to acknowledge and maybe even embrace all of our shortcomings instead of being delusional and just repeating to ourselves that things would okay, we're all perfect, and everything will all be fine."
I don't think having a positive attitude means you can't be a realist and take steps to avoid known hazards. Neither does it mean you should be delusional and just wish things to be ok. Being positive means you take active steps to effectuate a positive outcome in all your actions and reactions. Cynics are usually too sure of bad results no matter the probabilities and usually fail to take any proactive measures as they assume they will fail or fate will intervene and ruin things anyway.
The message I am trying to convey that while we live in a less than perfect world that has always had what seems to be insurmountable problems, humanity has so far managed to carry on and in some ways overcome. Look at the medical advances in the last 60 years, especially vaccines and even treatment for AIDS which was death sentence for so many years!