It's possible that technology could continue to advance fast enough to sustain future populations. In the meantime, humans have driven more than 300 animal species to extinction in the past 500 years, continue to increase the amount of CO2 and other greenhouse gases in the atmosphere, more than half of the world's largest aquifers are being depleted, total acres farmed worldwide are decreasing, and deserts are growing, all while human population is still increasing. The world probably hasn't had a sustainable human population since around 1500.
Necessity is the mother of invention.
Tens of thousands of species have gone extinct without man's influence.
CO2 is only 0.038% of the atmosphere today. Man is responsible for only 0.00114% of the CO2 in the planet's atmosphere.
You DO realize that the water on this planet is not being depleted. Water processing is simply a matter of energy, which will be a problem if we do not stop the current administration's war on cheap energy.
America has more new growth forest than ever. We pay farmers today to not grow certain foods.
Actually, if governments and massive entitlement programs continue to grow at their current pace, there won't be enough people to fund the needs of the aging population. Japan is in crisis mode...
https://www.washingtonpost.com/news/wonk/wp/2015/01/07/japans-birth-rate-problem-is-way-worse-than-anyone-imagined/Also, China ended their decades old one child policy.
You need to stop worrying about whether the planet will be around for awhile and start worrying about your children and grand children having to pay off your current country's massive debt.