“their numbers would perhpas get better and a different schools numbers would get worse”
Not necessarily so. There ARE enough boys on the planet for each and every girl (unless you don’t believe in hashgacha protis, and if so, the conversation ends right here.)
That of course cannot be the case, so its just a question of finding / matching the “overlooked gems” that are oout there. Do the “hard cases” (older, less glamorous, less than perfect dress size, not enought money / yichus) require more work? Of course they do. Will shadchanim work as hard as the single will work for themselves? Not so sure. So the best soloution for those facing an uphill battle is to do the work themselves.
But I’d still love to see the data on the boys.
As lakewood fellow said, there are plenty of chairs, just not in the room you’ve locked yourself into. Think out of the box and soloutions will present themselves