I F'n HATE you now. Really!
No not really... I actually agree w/ you. If you take any sealed environment it will eventually over populate, and die from its own waste.
Have you seen those glass balls w/ shrimp, and algae or some such... They do live for some time but they pollute, and die.
I believe the earth is the same. We are sealed in here. The most important thing we have done IMHO is to completely remove the Ozone layer. That alone has turned out planet into a Giant microwave oven. In the 80's the big talk was a hole in the Ozone. Today there is nothing left.
All the other crap could have been reversed/fixed. BUT the demand on the planet from Billions of people will lead to a major failure of our life support "system".
That part the conspirators have right... The population must be cut in order for life as we know it to continue.
Might I suggest a murder suicide pact... Everyone flips a coin to see who is who. I have a two headed quarter so I will flip for us, and I call heads.
This should go just fine...