First world countries are not overcrowded. Scientific progress (increase food production, improved medicine and care) is the reason you will probably live 30 years longer than if you were born 2 centuries ago.
Quality of life is far more important than quantity. Define "overcrowded"... First world countries are more crowded than they were 30 years ago, and (IMHO) the quality of life has gone down.
And as for your "increase food production"... We're force feeding chickens to be morbidly obese, pumping them full of anti-biotics so they don't get ill from living in squalid conditions. We're killing off the bee population with pesticides everywhere. These things are not good, and will only get worse as there are more people to feed.
The best way to improve your quality of life is not to look to science (Unless you're actually ill), it's to look to nature.
People living in cities are healthier and less obese than their counterparts living in the suburbs, rural areas, and small towns.
The best way to improve your life is to look to science. Please stop spreading ignorance around. You're actively working to hold society's progress back.
Is what the OP said, and it's false. I will not. The average may be 30 years longer, but that's a fairly meaningless statistic.
The fact that you were born today means that you will be shielded, either fully or partially, from many of the factors that made the average lifespan 30 years shorter 2 centuries ago, infant mortality included. The lack of these factors would then lead to you "probably" having a 30 year longer lifespan ("probably" in the statistical sense).
You could argue that a more robust statistic like a median would provide a better representation of the expected lifespan less drastically affected by outliers, but calling the 30 year difference in average lifespan "meaningless" is disingenuous at best and could represent a fundamental denial of basic empirical evidence at worst (the latter of which seems more likely to me judging from some of your other replies so far on this subject).