When I played previous version, I was preplexed:

I reduced pollution to zero. cleaned all pollution, why I still have to reduce population?

I thought it is hidden message: "aim of reducing population to save environment is wrong, it is not necessary to do"

However after update, this message became clear. Same time, author improved gameplay.

Actually, saveing enviromnemt is the global problem. Combined effort of majoity of people can resolve this problem.

===========

I like both idea of this game and gameplay. 5/5 is deserved.