Optimism is possibly the single greatest indicator of good mental health.
Pessimism is often a sign of the opposite. There are exceptions, a group know as defensive pessimists, who can go through life being pessimistic about most things without falling to pieces, but they are the exception.
If you accept that none of us know how the Draft will pan out and that A+ graded Drafts have bombed and F Drafts succeeded, then you can decide this:
Do I feel pessimistic and unhappy about a future that is unclear that is out of my control?
Or, do I feel optimistic and hopeful about a future that is unclear that is out of my control?
Presuming you don't get all happy clappy and verge into positive thinking (which by and large isn't helpful and not the same as optimistic thinking), then being optimistic just makes you a happier person, and science has my back on that.
It's your choice of course.
There is nothing either good or bad, but thinking makes it so.