Dear American,
Those who stay in EY longer because they did not get into shiur, is tiny minority. This does not apply to most groups of bachurim. As in, those who stay in America, learn in Israeli yeshivos, head to the Mir, Reb Tzvi, or really any place besides Brisk. Is Brisk even one percent of all yeshiva bachurim over twenty one? Now subtract all those that get into shiur within a year, as well as those that are not there for shiur. Also consider those that change their plans and come back or move on. additionally, those that are in Brisk for life are eligible to marry into Israeli Brisker families. So they don’t all affect the American Shidduchim scene. Besides for the serious guys who are not going to stop learning to close to twenty five to date no matter what yeshiva they are in.