That's probably the way we'll have it, but there will be artificial-natural habitat, eg. "reservations", that could grow to even be country-sized or half-continent-sized if we manage resources right. (Though probably they'll be smaller since we're going to have to some pretty large scale heavily-engineered-and-very-unnatural-agriculture to prevent famine in the face of climate degradation.)

The second option sounds somewhat enticing... but it would likely severely diminish speed of technological progress, hence diminish our even-longer-term changes of survival (think encounter and warfare with alien civs etc. - the universe is huge and if we/our-mostly-artificial-descendants survive long enough we'll have to compete with strains of life much more virulent than ourselves today).

Also, the kind of technological delay you're talking about there would be a couple of decades at most, when it looks like you're talking about thinking in terms of centuries. If anything, we're slowing down necessary technological advances to maintain the status quo long past the point where it's tenable.

"Climate change" is a red herring; we can "fix" the increasing temperature problem and yet deforestation, pollution, and overpopulation will still destroy every natural ecosystem on the planet.

The object of power is power and any claims of a cause are illusions and deceptions. React accordingly.

There are potential forms of alternative or third position government structures that allow for just as much or more personal freedom than current democracies, and yet can preserve our natural ecology. It just requires an accounting of destruction of commons, where untouched biodiversity is valued by the people of the state.

If we have the power to absolutely destroy the natural environment, we also have the power to protect its beauty for future generations rather than selfishly destroy the earth.

Plus that's kind of the opposite of what you're talking about, as most of the women are infertile.