Jordan has the lowest suicide rate, I remember. Something like no suicides since 1970, according to a mid-90s records book. So there's low population density for you.
It's more competitive today than before not because life is more difficult, but because people have more potential to gain money and power, and they want to gain more. I mean, it's possible to totally slack of and land a job for $10,000 a year. In the US, that's considered to be at the poverty line, but that's considered middle- to upper-class in most parts of the world. You can still feed yourself, buy a car, buy a TV, and so on. In fact, you can live in a 100 sq. ft. apartment and play FreeSpace Open all day on a yardsale computer. But because education is so readily available today, people have plenty of potential to expand beyond that, and they try to do the best that they can. Compare this to just 200 years ago, most of the population was rural, your place in society was to be a farmer (or a similar job), there was little potential for you to go to a good university or advance much at all in life. Urban workers faced a bit more competition, and had a bit more potential to excel, but even then, they had little chance of making more than a little over minimum wage during their lifetime. So everyone just relaxed, there was no need to be competitive as it wouldn't get you anywhere.