If you are e.g. A war correspondent and that's your job, you're probably going to have mostly negative sentiment stories. Similarly If you focus on reporting child abuse topics, similar. If your shtick is to embed yourself in poverty areas and bring true stories, it won't be lolipops and rainbows. Outside of journalism, same thing. There are jobs where you get exposed to wonderful things day in and day out, and there are jobs where you get exposed to bad sad stuff. and everything in between.

Particularly if your goal to be in journalism in the first place may be to change / improve the world, you might focus on things that need changing / improving.

Finally, outside of some very specific places, in a lot of the world things suck more than they don't.

I don't know if that answers your question or you had a different question / point to make?