I know a couple of optimists who seem very interested in the notion that all the work they’ve done so far has created a good outcome instead of one where people have to work very hard to do basic things.

“Everything is awesome,” in this context, is alienating, or if you prefer, gaslighting.

And self damaging. Nobody wants to talk to them about real problems because there is no safe space for candor. So people talk to the pessimists, creating a rift. “I haven’t heard anything about this,” has been uttered more than a couple times. No shit Sherlock. Who would talk to you about problems like this?

I have seen the opposite personally - people who push optimism as less successful but cheerfully repeatedly making terrible foolish mistakes. From "I totally won't wind up homeless in LA if I move there to make it as a star with no acting education or experience." To "If I stay loyal to this horrible person who abuses me they will get better."

Pessimists I have seen generally as more secure from planning for the worst perhaps to overkill extents but less happy.

The snarky summary is "An optimist is a million dollars in debt, losing money every day and thinks it will get better. A pessimist will eventually have a million dollars, feel precariously worried about pending disaster while their true greatest risk is their urge to commit suicide."

There were many studies that have found the opposite of what you have found: https://escholarship.org/content/qt1k08m32k/qt1k08m32k.pdf

This is measuring happiness, not optimism. There's probably some overlap, but they're not the same thing.

"It is not that being optimistic leads to success..."

How do you know the casual relationship?

People's perspectives are shaped by the outcomes of their actions.

I can imagine if all you have is positive feed back loop, you will see everything will just keep improving endlessly.

Which is why these perspectives are what they are perspectives. They are not real world models you should live your life by.

In real life you must deal with the situations as they are.

There is certainly a correlation between the two. But I think our general sense of optimism towards life is set at a very early age. Take Elon Musk who, as a kid, was always described as an optimist despite his unsuccessful childhood.