hello99,
You mention: “focusing on superficial traits, money, problematic personalities, lack of experience and guidance, shadchanim, unmarriagables, ease of being good girl over boy”.
These would explain why there are so many singles, but not why there are so many more girls than boys (a fact clearly observed by shadchanim). The fact that there are actually about 5% more males than females (a fact which I just read in this thread), if applicable to the frum world, would make one wonder then, why there are so many more frum girls looking for a shidduch than boys. This should force one to realize that the main issue is age gap. I can’t understand why you would think that it only “may” be a minor factor, when it is so clearly a major one. The facts of a 3-4 year age discrepancy with a 3-4% annual population increase leads to the inevitable conclusion that there’s a gender discrepency; I can’t begin to understand how this could be “debunked”.
I agree with you that there would be a tremendous drawback to having boys get married when they are not yet mature enough. As to your issue with making girls wait, that’s only indirect; the direct attempt at a solution is to convince boys (who are ready) to see “slightly older” girls. Although this would obviously slow down the rate of 18-20 year old girls getting married, I don’t think anyone is telling them that they must wait.