They could work if they want to. The issue for many is that they don’t want to be in a office with women who they feel are dressed immodestly. They could also go through the army process and get out on low profil, many do this. This is as if they served as far as job market. Also I don’t even think it matters. if someone is qualified and skilled they can get a job.
Many charideim have moved to CHu”l all the time and vice versa. Alot depends on their Chassidus and their comfort level.