I think it will be solved - by nature - if humans keep proliferating. There will utlmately be a shortage of space, water, food, medicine and many other resources. Mankind will have stripped the planet of all of the goodness - all the carbon storing flora will be gone - oh - and I'm sure there will another virus or two to further control the population.
I agree with your assertion that over-population is a significant problem, and I think that it is women that fundamentally need to address this problem as it is they and they alone who bring new humans on to this planet. Women need to be educated when they are young children to seriously think about the effect of the numbers of children they might bring into the world. This obviously needs to be on a global scale and especially in societies where women typically have large numbers of children.
The days of "be fruitful and multiply" (Genesis 1:28) are over..... may be it should read - "be fruitful and keep the population to a sustainable level". We need to ensure those that are born are fit and strong and hopefully are able to work long into their later years so there might be less reliance on sheer numbers of people.
In fact, it saddens me when you hear about women having multiple births of 4,5,6 or more children and think it's wonderful - given the numbers of starving people on the earth and the current state of the planet and where it may be heading.
It is the ever increasing population levels that are driving demand for more and more resources that are becoming scarcer and scarcer. It is the ever increasing population levels that are causing more and more pollution in our seas, the air that we breathe and the atmosphere that we rely on to keep our planet safe
Population and population control is a female issue - ultimately it is women that are the problem and it is women that are the solution.......
Answers on a postcard please......