But they also reflect personality; it's not a necessity even in negative times.

For an example of how to tackle negative topics with a less negative approach, I recommend Dustin Arand's stories. I almost always leave them feeling wiser and more hopeful, despite having spent a good ten minutes (especially if I pause to think and read other background material) plowing through pretty negative topics.

For an example of how to tackle negative topics with bleak despair...uh...wait, why would we do that? But you can assuredly find examples far more in this direction than your own stories should you wish.

Regardless, it's a confluence of both the times and the personality (at least one's public persona). If one holds one's own personality fixed, one can say: the times are responsible for this. But personalities aren't completely fixed, so there is always some degree of dual responsibility.