CO2 is higher than in the past several million years and we're still adding more at our usual pace. We've killed 60% of wild vertebrate life since 1970, wiped out a large percentage of the insect population, and we're continuing the practices that caused that as well. None of this can go on forever.
Almost everybody misses the main finding of the Club of Rome study: if you model a simple assumption that resources get more expensive to extract over time and environmental destruction gets more expensive to deal with, you don't get a gradual decline. You get continued improvement up to a peak, and then it suddenly crashes down.
What's really toxic: enjoying that run up to the peak and assuming everything's fine, instead of buckling down and fixing the problems before it's too late.