Wow, I must say, I have thoroughly enjoyed not only the lively discussion between you and jasonhernandez74, but the input from all contributors to this topic. A truly humbling offering of food for thought 
To add my 5 cents then:
I have to agree with alot, perhaps most, of the points made by Jason. If one takes a really pragmatic view of what is happening today, the stemming of the global population and the resource use and waste this entails actually depends on factors which are largely out of the hands of grassroots conservationists entirely.
What will ultimately decide the fate of the last few percentages of arable and biologically productive/ diverse land remaining, is the progress made in key theaters in the global south around millenium development goals like access to education, equal opportunities, and safe and sustainable housing and livelihoods; amongst a plethora of variants like legacies of political and social instability, and insurgencies and extremism. These issues are out of the sphere of influence of all but the most well-connected and established conservationists, and even those people will have relatively little sway in the grander scheme of things
Maybe all these loose ends will tie themselves up completely? Very unlikely. Partially? Maybe, or maybe lesser still. But you can be assured that whatever the eventual outcome produces, Planet Earth will inevitably lose more and more land which is meant to be “set aside for non-human settlement” for the purposes of accommodating those species which man struggles to live with, and land that has long since been developed or encroached on will be further denuded from increased drainage, reticulation, paving, landscaping transformation, and pollution.
Already in biodiverse cities in the south such as Cape Town, there are huge tracts of lowland which it is feared have lost their dormant native seedbanks as the effects of intensive urbanization and trophic pollution become too great to bear for alot of species. Even the hardy species that remain, those that are little effected by severing themselves from what were once complex ecological webs, will take many dozens or hundreds of generations to adapt to niche deprived human environments. In terms of communal adaptation and the evolution of related plant/ animal assemblages, the time-scale needed is more of the geological variety, one in which human dominance will have long since been rendered irrelevant
One is tempted to then ask: How much can society shift the ‘natural’ goalposts before they land up outside of the proverbial stadium?
I do think a bigger picture perspective like yours is helpful to longer term conservation in that it can break us from the trap of becoming sentimental for the way nature “used to be” and the networks and species that have been lost along the way. Being someone who was brought up in the school of in-situ conservation first and foremost, I may obviously be a bit biased but I really do believe that all efforts should be made to normalize human settlements not living off of diverse habitats, but thriving WITH them in a mutualistic manner (humans living a rich and productive life on land which is in turn, bolstered and better equipped to adapt to change). From where we are now, this may seem a bit pie-in-the-sky, but even small steps collectively can make a considerable difference. A good starting point in this endeavour would be to tackle the often pernicious “kill it with fire” and “not in my house” subtexts which are perpetuated and echoed to and from urbanites online. The reasons why we developed a deeply-rooted psychological fear of animals like spiders, snakes and rats are completely moot in todays context, and hence we need to instill a healthier outlook in society’s collective consciousness.
There are also alot of technological breakthroughs on the cards to help livestock agriculture and apex predators co-exist, and if we are to preserve our beautiful world and all its contents, we will need as many of these kinds of breakthroughs as we can get!