I don't think that equating pessimism with self reliance holds water. In fact, I suspect the opposite is true, because a more optimistic outlook leads people to do things, and the more one does, the more one learns and the more self reliant one becomes. Self reliance, in turn, breeds self confidence, which again translates into doing things, rather than just being an armchair critic. It's a growth spiral, whereas pessimism is a downward spiral.
And again, it's not what one* person can do; it's a matter of what many individuals, who are all trying, can do.
*Although many people do indeed do significant things, all by themselves.
If I remember correctly, in the past you've mentioned that you do volunteer work. That's great, and I'm sure has more of an effect than you realize. Acts of compassion have a ripple effect.