Most people who actually understand climate change also don't expect beachfront homes to be under water in the next few years. It's a slow death/dramatic change of our planet, something that will take place over the next few generations, not the next decade. And if you - or anyone else - thinks it will only impact the poor, you're grossly mistaken.
Perhaps more to the point: our world is stuffed to the rafters with complex adaptive systems--both man-made and natural--themselves threaded together by positive and negative feedback loops, punctuated equilibria, and participants trained on making decisions under these conditions.
We don't know which threads will snap, nor when, nor where. We don't know how the other systems and participants will react to the ripples. We don't know if, how long it will take, or where disrupted systems will settle into new equilibria.
In the face of uncertainty on this scale, I think there is some value to catastrophizing. We do this with uncertainty all the time. We imagine threats (both banal and catastrophic) to our systems and game them out. We make plans and run exercises. I'm not sure it's a bad idea, per se, to be gaming out dead-end scenarios.
This is not how I would characterize the last 300 years of our efforts as a species.
Characterizations are not mutually exclusive.
There's no catch clause in the universe's code to stop our most-impressive inventions from ultimately killing us, our most-creative disruptions from sundering our societies, or our most endearing traits from tucking us neatly into the geologic record.
I lived near a barrier island that would get hit with hurricanes each season, and every 5-10 years a storm would devastate it. Despite that, property owners would rebuild their several million dollar vacation homes exactly where they last stood, but raised just a little higher than the last time.
I don't blame them, it's an amazing spot in the summer.