Unfortunately the fault is of the Rosh haishivas and Rashei Kollelim. It’s against their intrest that yeshiva young men should leave the yeshivos and kollelim and seek work. Many Rabbis that make their living from yeshivos and kollelim will loose their jobs.
They make a point in putting down working ballei batim, they will discourage yeshiva studants and seminar girls to marry not only working bachurim but even if their father works for a living he is not a “ben torah” in their eyes and not worthy of marrying a ben torah.In some girls seminars in US and Israel only girls of “Bnei Torah” = non working are accepted. The daughters of people that work are considered second hand.
Before the WWII war in Europe only in Lithuania did men learn the whole day and their poor women had to scratch a living, the Polish and Hungarian Jewish men were mostly balei batim talmidey chachamim that dedicated a couple of hours to learn every day but worked or did business for a living. The students of the great Pressborg yeshiva were known talmidei chachamim but most of them had trades or businesses for a living. That is also the custom of the chasidishe in US. Unfortunately the litwishe Rosh Yeshivas dominate in the Yeshiva world (specially in Israel) so they impose their derech on all yeshiva students