Yes. Either people take care of it in a sane manner by having
less kids, or nature will take care of it. We will hit
critical resource constraints of some form.

We already are to an extent. Remember when everything in the
store was made of metal? Now only luxury goods are built the
way consumer goods used to be made.

There is plenty of energy if we go solar, but we have an era
of permanently high energy prices until the switch happens.
Not to mention the effects of massive CO2 release.