Cynicism is easy.
Cynicism is toxic.
Cynicism is deceptive.
A cynic believes they have corralled all of reality into their own little brain and determined that things are bleak indeed. There is, however, a very big problem. No one can know all reality, except God. And God tells us that a mark of being a Christian is hope.
So, since no one is omniscient, no one has the right to be cynical. There are all kinds of realities the cynic does not know about that would change their pessimistic outlook.