Why not? What do we lack, or what would hinder us from sustaining current or projected population growth outside of the administration and methodology of extracting resources?
Well, where do we start? The unit of food production per square metre of land is a limiting input - sure biotech *might* squeeze a few more units out but when you follow any curve of technology development the upper-reaches are exponentially more expensive to achieve than those below, which in itself in a limiting factor. Then you have to account for the fact that gains made over the last 60 years have come about as a result of the Green Revolution which harnessed the energy from fossil fuels to produce intensive nitrogen-based fertilisers. Take Australia as an example, as an old, arid continent the soils were very thin and impossible to replace as the landmass has essentially eroded as much as it possibly can without renewed tectonic activity. When t farmers arrived and started growing sheep and wheat they very quickly created dust-bowl type conditions that saw the soil blow away, they were saved by the advent of the GR but now you essentially have a situation where the vast food-bowl regions exist as a substrate into which nitrogen based fertilisers can be injected into thus ensuring crops can be grown. All of that relies on access to cheap oil which is a non-renewable source of energy, production of which is rapidly peaking, further increasing the costs of extracting more productivity from the system. Then there's water, that is another clear hard limit built into the system, all across the planet fresh water stocks are under incredible pressure, which is being exacerbated by the changing of the climate, and which brings us to the problem of outputs in the system - the planet has a finite ability to absorb the waste products of production. So you have a situation where demand is steadily increasing with no signs of abating for decades to come, meanwhile the cost of increasing supply is increasing at accelerating rates that are often exponential in nature. Basically, the whole global food system is based on the premise that we as a species will
always be able to find technological fixes to overcome limitations, which isn't an immutable law of nature - indeed it violates any number of physical laws - it is an assumption based on taking a narrow window of data, based on a mere 200 years of exceptional growth that was entirely premised on a sudden and incredibly unusual access to reserves of cheap energy, and extrapolating the trend indefinitely into the future. Which is the planetary equivalent of doing this:
And even if we were to get away from the long term risk assessment for just a moment and go back to the idea of exponential cost increases to achieve incremental production benefits in an environment where demand constantly growing. We live in a highly interconnected global economy where a hiccup in one region can cause untold chaos in another. Just a few years ago, back in 2008, there were a few hiccups in the global food supply chain, Europe had an exceptionally hot summer (climate change) that knocked out their grain crops, while simultaneously the US was diverting food crops into ethanol production, the combined effect of which rippled through the global grain price causing staple crops all across the less-developed world to triple and quadruple overnight. Suddenly, a dirt-poor family in Bolivia couldn't afford to buy the corn or quinoa that they relied on to survive and were pushed even further below the poverty line. While such a minor price correction probably didn't even register to most rich, entitled westerners unless they happened to be trading in primary resources market and saw a dip in their portfolio, for vast swathes of the planet's population it resulted in very real and tangible suffering. maybe not quite starvation and famine but the point is that the global food market is incredibly sensitive to price-shocks and it wouldn't take much more of an impact before it does result in very real and very serious consequences that could result in the deaths of millions of people, the majority of whom live off an annual income that would be lucky to buy you or I a nice fat steak at TGI Fridays. So in an environment where demand is rising, the costs of wringing a few units of production is growing exponentially, in a system with all kinds of feedbacks and is not at all resilient to shocks of this nature, you don't even have to be talking about a MAJOR crisis (i.e. when that actually cause rich, entitled westerners like you or I to sit up and take notice) before your dealing with consequences of arrse-fuck proportions
The Cornucopian assumptions built into our economic system are so staggeringly absurd that it doesn't take a huge amount of thinking to see how flimsy the whole edifice really is - the worst of which is that we can simply take a very limited data-set and extrapolate into eternity. Just because a crisis of apocalyptic proportions hasn't happened yet does not mean it cannot ever happen.