It's not true. Storypick.com earns over $7000 from adsense.
There are many other blogs in India (trak.in, yourstory.com, labnol.org, phoneradar.com) that make more than $5000 a month.
Now, mashable makes more than $100,000 from adsense alone.
You need to have at least 80,000 visitors daily to make $5000 from impressions. If you get decent amount of clicks, you can cross that mark too.
One month back, I was just browsing this forum and I saw a guy showing his earnings (with screenshots). He made over $1000 from adsense and $1,400 from affiliate marketing.
It's not a dream. It's possible. You can do it if you really want. to.