I have a close friend who was a “Teen at risk” back in the day. He dropped out of yeshiva, went to school, graduated and even got his CPA. By that time he was growing out of his adolescent rebellion, and settled down and married. Moved to Israel, learned in KOllel for 3 years and came back to the US. As he was licenssed, he was able to become employyed very quickly. I think it was more the license than the education. Just an education and a degree, and then several years of removal from the olam hamaaseh, it is difficult. But the license was a very tangible piece that made a very big difference.
I think one of the main reasons the yeshivos don’t encourage this is because once one is out in the world, and is to’em the ta’am of the world and everything in it, it is very difficult to “put the genie back in the bottle”. People will leave yeshiva, fully and realistically expecting to return, but after they are exposed to the velt, it never happens for many people.