Lomed Mkol Adam:
For all the 30+ years who “rotting away alone in rented basements in Brooklyn, without any social network, who have already given up calling shadchanim.” there are the same amount of boys who are eshiva with no network, who have given up on shadchanim as well. Most guys don’t resolve to hysterics though.
Also, as you mentioned “without any social network”. So it is their problem that they can’t figure out how to do something for themselves and they are relying on others, who seem to be incompetent in the shadchan area (shadchanim).
The problem is not the age gap but the lack of singles who are capable of doing something on their own and are relying on others for everything. Tell those 30 year-olds to mature and do something for themselves.