DaasYochid-
It looks like we’re going to have to agree to disagree as to “what extent of the problem is age-gap related, and what extent is from other causes”.
I agree that the “age gap issue” is a significant issue but I still believe that it is not the root of the cause, it’s a byproduct.
If there is a realistic way to get guys to drop their insane demands then that’s good news. If it’s been tried and has been showing some signs of success then I stand corrected and hope it continues. (I’ve been out of shidduchim for many years now so I wouldn’t know either way. Even when I was in shidduchim, my friends and I were not the type to make ridiculous demands.)
Getting rid of the stigma sounds like a great idea, without this I believe that there will always be somewhat of an age gap.
However, the nasty shadchanim and their despicable tactics, have to be brought under control.