Current population is at 7 billion people and by 2050 expected to be 9 billion. Finding resources is getting harder and harder as time goes. For example oil, a drill must dig even deeper to find it which increases the cost. So many resources are being used in the planet. Like water, 50 gallons of water is used to gain one gallon oil. Many forests are being cut down to grow crops for food to food the world.
Personally I think resource depletion is a problem, but there isn’t much that can be done except limiting the use to anyone. The use should be controlled so the planet has time to create more. Natural Resource depletion also seems to be a problem caused by overpopulation which also should be limited. It keeps everyone in line and fair so their isn’t as many issues in the future.
http://www.bbc.com/news/business-16391040