I find that optimistic people, often get let down, where a pessimistic person is like, yup. I knew it!

No, I feel sorry for them. They always see the worst in a situation, instead of recognizing and appreciating the positives. They are always stressed and unhappy.

No. And an optimist isn't "good".

There's dark and light to everything, neither are definable.

I hate the terms optimist/pessimist because it implies only one way or the other.

Say someone has a severe illness, some days you can be strong, some days you can't. And people will judge you like hell on your bad days, label you a pessimist and call you annoying. Game over.

The day people realize life involves both is a day of peace and balance.

No just exhausting to be around

Your attitude is your choice, to see the glass of half filled... Half empty... Or just half way, it's your choice to see any way you want. I'd call myself a realist... Looking at my day, I know it could always get worse, so be thankful where I'm at in the day

Not bad but I view them as unhealthy and not someone I want to be around.

an optimist believes people do the best they can to create the best possible world to live in.
a pessimist fears this to be true.

It is what it is. Good or bad is irrelevant in the absolute sense. But if the pessimism in a person is strong enough that it causes them pain and even stress induced illness, then it's a bad influence on themselves. Also people do not like to hang around people with an always pessimistic view. It is a downer. That could cause a person isolation and again, not good for them.
That is true of any extreme ideals and beliefs.

Optimism is the state of mind in the young.

Pessimism comes with age.

Nah, not just bad, it's way more complicated usually.

Being pessimistic isn't bad, but it isn't good either. I believe you must strike a balance by acknowledging both the negative and the positive in the world.

Just annoying usually

Not always. They tend to be more honest about things.

The optimist says the glass is half full.

The pessimist says it’s half empty.

The realist says it is full of piss.

Not bad, but sometimes difficult to be around if one is trying to move into a more positive headspace… 🙁

I don't know......maybe? ;-)

Pessimism is like a virus. A person who deliberately spreads his or her virus is bad🤔.

No, just preparing for the worst.

I would answer this post but I'm afraid something horrible might happen if I do

I think being overly negative about everything and being overly positive about a bad situation can both be bad.

Think positive and not negative, its probably healthy to be a bit pessimistic but not all the time.

pessimists are liars and liars are pessimists