>> "God grant me the serenity to accept the things I cannot change, Courage to change the things I can, and Wisdom to know the difference."
Your post is wise (or at least, it resonates to my best thinking on it which boils down to the serenity prayer as well.)
But I disagree that the two things in your first paragraph are equally bad.
If you think nothing is in your control and just blame others all the time - then you pass up every opportunity to make your life better, and I agree this is extremely common.
If you are on the other extreme and think you can control everything - you do end up tilting at windmills and wasting a lot of time and energy, but you also end up doing things that make a real difference in your life. It's a strategy strictly dominant to passivity.
Thus blaming others is always worse and I agree with your paragraph #2 and #3.