We've grown dramatically in number; what impact might that have? Our population has tripled in the last century with the majority of the increase occurring in established urban areas. More than half of the world is now urban.
World Health Organization: The urban population in 2014 accounted for 54% of the total global population, up from 34% in 1960, and 14% in 1900.
Increased population and density have changed our culture.
We began as rugged, independent ruralists who could build anything, fix anything, and make do with what we had. Since the beginning of industry, we've become a culture of consumerist/ specialists. Everything we do takes hundreds of skills spread across hundreds of people. Or thousands. From getting food on the table via stores and transport to building airplanes via dozens of suppliers and producers and engineering organizations, we're extraordinarily complex and interconnected. Most of us couldn't last a month on our own in the wild, of course. And we have so much stuff, but we keep buying more.
We were a nation of younger folks not too long ago. We've changed. Now there are so many older people in the middle of everything. :)
There's a benefit, perhaps. The 50 year+ folks are stunningly productive. They can do in a day what the 30-somethings will struggle with for a week.
It's worth seeing the things that have changed with some clarity. Old ideas may not fit, old solutions may not work, and the way forward will not be like the past. Everyone is scrambling to keep up. Schools, governments, churches, and families are pressed hard to cope reasonably with the high-speed changes that sweep us all along like a flood.
We do get to choose our own goals, however. Our purpose can be noble despite the most tumultuous of times.