What it costs in resources to maintain the modern lifestyle and civilization, is quite finite. We learn new ways to spend and consume, and innovation in sustainability is not the priority in a Capitalist economy.
To become sustainable the population will have to accept changes to lifestyle which they have not shown any sign of willingness to do so. Rates of e-waste increase faster than the rate of e-recycling. As long as capital and profit remains at the incentive it's at now, there likely will be little change.
Ask yourself what will occur when natural resources are no longer feasible to supply at the rate they are now, such as Oil or vital resources to produce electrical components.