In my opinion, dating sites are still extremely efficient ways of meeting people. I exclude eharmony, both from personal bias, and from the fact that they don't allow you to really search the database.
After you leave college, real life meetings become much more complicated. The bar scene is a lottery. How likely is it that you'll actually coincide in time and space with somebody who you would be happy with, and then how likely is it that you'll even get to talk to them if they are there when you're there? Grocery stores and other non-traditional meeting places, I personally avoided bothering women in, assuming there should be some neutral ground where a woman might wish to be left alone.
For me, I wanted college educated women who had opinions about politics and whose opinions I shared. I wanted women with no children, who lived within 50 miles of me and didn't smoke or do drugs, but who did drink socially, wanted children, had traveled the world some, and were not strongly religious. I wanted women who enjoyed outdoor sports such as scuba, skydiving, and rock climbing. I wanted women who didn't own small yap dogs.
Can you imagine bumping into women like this randomly? But with a dating site, it became so much easier.
I still went out on a lot of dates that were bad matches, but I definitely skewed my chances of finding somebody I could respect and have fun with by taking the random chance aspect out of the equation.
EDIT: The article doesn't actually disagree with this. It's saying that paid dating sites will lose out to unpaid. I was responding to the HN title which derides all dating sites.