It is said that the current total population of all humans can be close-quartered into roughly the size of the state of Texas.
This doesn't take into account the bio-fuel, energy, and resources needed to properly sustain all humans and have us thriving. However, this does point out that there is hope and we aren't doomed because in reality, we haven't run out of space. But I do agree that we should take measures to not overpopulate beyond what we have in front of us.
All developed modern nations and societies have one thing in common: a low birth rate across the board. Every single group of immigrant that has come to the USA, upon becoming more educated and become more modern-thinking, has decided against having more than a few children, if any. Just look at the older Hmong generations and then look among your 20-30 year old Hmong demographic and it's obvious. I see so many Hmong couples with just 1-2 children and seeing mid-30 Hmong single un-married people choosing to be childless is not that rare. So, there is hope!
I really hate young Hmong brothers who have 5+ kids because "I want an army of sons" or "I need someone to take care of me when I'm old or pay my funeral". Or the most pathetic and despondent of all: "if one dies, I still have a few more". Wow, just wow. It is so selfish and primitive. This kind of thinking is why we are in the position we are.
Like comedian Bill Burr says, "Don't you think after 2-3 'ain't shiiit, didn't invent nothing' kid, that you're not going to make a genius? You got a family photo of 15 kids. That's an environmental disaster...and you framed it!"