Think of all the things that took hundreds/thousands/millions of years to develop and mature, which humans have managed to destroy in relatively short order.
Every 50 years we cycle out an entirely new batch of thinking humans. What cognitive legacy is it exactly that you think is going to be self-preserving?
Plato said the same thing.
You're talking about system altering the environment. GP was talking about the system altering itself. The system is a massive self-stabilizing collection of feedback loops. Unlike the static environment[0], it's incredibly hard to intentionally move such system to a different equilibrium. If it weren't, we'd already solved all the thorny world problems long ago.
--
[0] - Any self-stabilizing system that operates much slower than us - such as ecosystems or climate - is, from our perspective, static.