There are many fine, wonderful bachurim learning in YU, who have graduated from Touro and other colleges with the ability to go out and earn a parnassah. They are also very shtark and very dedicated to torah and mitzvos. I suspect your sister is more concerned about not doing the cookie cutter thing and is worried about answering to her friends than anything else.
To the person who made the comment about growing up in a home of torah, while children whose fathers are lawyers, doctors, cpas, store owners or whatever else it is people do for a living these days, can’t say my father worked on a ketsos all day, they can also grow up in an environment of torah. They know abba (dadd, tatty) is out of the house at 5am to meet his chavrusah at a kollel boker (how many who sit and learn all day know what 5am looks like?), they know that daddy goes back out to learn after 10pm for an hour after he helped with the homework and bedtime, they know shabbos and sunday when there is no work for abba to go to he learns with the kids or is at a shiur. Legal holidays when no work, he is at a shiur (how many yarchei kallahs exist during bein hazmanim?) or with his chavrusah. This sends a powerful message about the importance of torah to children too. More powerful, I believe, than the 9am minyanim for shachris that pop up during bein hazmanim.
Balabusta, there are many fine bachurim out there for your sister, the ribbono she’ll olam already called out bas ploni liploni, hatzlacha in meeting up with him quickly.