That isn't accurate at all. Books have been written since the early and mid-20th century about the effects of a technocratic society and the limits of growth, and those analysis and predictions have certainly come to fruition in various ways.
What is scary about the climate and the environment is that they are highly dynamic systems. If anyone has studied dynamical systems, there are certainly points where everything is "fine" and then boom, a sudden critical point is hit and things go off the rails. The worry is that we seem to be constantly teetering on a critical point. Or we are simply in slow motion destruction. Or both.
Take any closed ecosystem (which the Earth is) and imagine doing to it what we do to the Earth. Is it any surprise things are going off the rails? Resources are not infinite and almost none of them are mined/gathered without major consequences to the environment.
Have you watched any documentaries? Animals and plants are struggling heavily in a myriad of ways and just flat going extinct at increasing rates. Glaciers are going away. Oceans are poisoned and hypoxic. Animals and even humans are filled with microplastics. Technology and capitalism is ripping society apart in a way in which a certain class of people have their thumbs over everyone else. There are literally plastic rocks being formed. Weather events are getting more extreme. Wildfires are increasing.
> objectively, none of those "whats coming" have happened
Search for any of those things and please tell me you still feel this way. Even something specific as a search for "birds filled with plastic" will show that this is not true. Does this look like things have not objectively happened with the climate? https://www.greenmatters.com/weather-and-global-warming/pict...