It's nice to be optimistic. I really don't see any downside. Except...
When it's a lie.
I hear people today saying that if you just believe hard enough that things will get better, then they will. That's not true. That's not even close to true.
Don't fall for this flawed idea of optimism.
Here's the deal. Sometimes life is hard. Sometimes it's hurtful. We all go through self-inflicted trials and trials that we don't understand. It's going to happen. When it does, you don't want to hear someone preaching blind optimism. It's not helpful.
Blind optimism is not constructive, it's not empathetic, it's not real, it won't help you connect with people and it definitely won't help the hurting.
Build people up by being optimistic in the right way. Be honest and sincere. Encourage people and truly evaluate their needs. Sit and talk with them. Learn about them. Learn with them. Solve problems together. That's the kind of optimism that we need. True relational optimism. Leave the lies for someone else.