An organism that breeds quickly and eats anything you put in front of it will survive nearly anywhere, because the requirements for its survival are simple. It doesn't need a lot of specific conditions in place to keep breeding. Such an organism can eat nearly anything and keeps breeding regardless of whether the environing area can support its offspring, so it spreads like the Plague and soon it's everywhere. When there is little food, mass die-offs happen, and then the process repeats as soon as a new source of food is found. Yeast reproduce quickly until the alcohol they produce kills them, for example. By contrast, organisms that are more complex and have specific needs are easy to kill, and much harder to keep alive. A bird that nests only in mature trees and has a specific diet cannot live in the little copse in your suburb, because it must have very specific conditions in order to stay alive. This is one reason you see the same kinds of animals over and over in suburban neighborhoods, because only species that can eat leaves and garbage and live anywhere can live in such a place. You see deer, squirrels, rabbits, the same few species of bird, and maybe one or two other kinds of animal that can eat anything and breed quickly. If you want a lot of biodiversity, you need a complex ecosystem with lots of niches to fill, so those specialist organisms that have specific survival requirements can have a place to fit in. There is a thing in biology called the competitive exclusion principle, which states that, if two species are competing over one resource, one of them will be driven to extinction; accordingly, if there are very few ecological niches, very few kinsd of resources, you end up with very few species. For example, if all you have is huge amounts of one kind of food, the landscape is eventually dominated by one species that eats only that kind of food. If you homogenize the world, if you turn everything into a giant suburb, you lose the specialists, the species that occupy unique niches. A homogeneous ecosystem with a low degree of complexity will support fast-breeding omnivorous pests and little else.
The point of this little philosophical excursion into ecology is that, taken as metaphor, this can illuminate something about human society, but first, we have to lay a little more groundwork. When we began to industrialize in the 1800s, we decided that standardization as the coolest thing ever and began standardizing everything. Fast forward a century or two and we've standardized everything - everything! Whether or not you're a good person is decided with reference to your "mental health," which has, in the United States anyway, its own special rubric (the DSM). Whether or not you're a good thinker is decided by whether you jumped through the appropriate hoops to get the right certificates. This standardization has helped in some areas (medicine, technical fields) and absolutely killed others (everything else).
Now, given the two observations above, what should we suspect about human society? As I said above, homogeneous ecosystems favor fast-breeding omnivorous pests; a simple homogeneous environment favors vermin because it lacks the nuance to support any organism more complex, which makes such environments boring and depressing. And, since industrialization, human society is just such an environment, in a metaphorical sense. So, what kind of person is dominant in our time? Sure, there are thinkers and writers and leaders, but they're all just people who jumped through the right hoops. A rat with a professional certificate is still just a rat.