I believe there are different types or modes of thinking. Some tend to avoid negativity, others live through it to anchor in reality.

Also, maybe it’s subjective, but all my friends who are negative-aware and embrace cynicism (not necessarily follow it) have much better sense of real life and of characters than all my friends who believe in all good things and are optimists. The former tend to be business people, the latter are all hired workers.

It depends a great deal on the nature of the negative thought.

For example: spending hours obsessively thinking about death and dying and infinite nothingness isn’t helpful in my opinion.

But avoiding thinking about a mole you might want to get checked out at the doctor is a bad idea.