If you’re thinking of nukes, we had New START, SALT, NPT, etc. and a shit ton of activism which significantly reduced the threat.
If you’re thinking of past claims that we’re “past the point of no return” for climate change, those claims were correct. We passed the point of no return for avoiding extreme weather due to climate change. Then we passed the point of no return for 1C of warming. Now we are nearing the point of no return for 1.5C of warming. Things are getting worse for the climate, which is why people keep saying that things are getting worse for the climate.
That said, apathy is counterproductive. We need hopeful children and adults to drive political and technological change. Therapy or other tools for reducing anxiety (e.g. exercise) could help people be hopeful.