Maybe a better question is: why are there so many more men than women on dating services? The ratio seems completely out of whack. It's not like there are 10 boys born per every girl, so somewhere along the way the women are filtering out. Perhaps women prefer face to face interaction?
These studies seem to be focused on a symptom instead of the cause.
Yes, that's the entire point of the original question and my response.
These comments are regarding mainstream dating platforms where male to female participation is reasonably balanced (or at least not exponentially imbalanced as you seem to believe). That massive imbalance is present in the matching.
One answer can be found in census data. The number of childless male adults is almost twice of that of female adults, but the desire to have children has been found to be identical among women and men.
What's certainly clear, and the data released by OKCupid bears out, that mean invariably send messages to women much younger, while women are more likely to message someone closer to their age.
Maybe the real advice to men is to pursue women closer to their age and leave the 20 somethings alone.