> Just a lack of other goals for which to substitute.
Ding ding.
I've mentored students/grads from aforementioned prestigious Universities and most of them just genuinely don't know what they want
After a few drinks, many have voiced a fear of there being so many options in life and not knowing which would be more fulfilling for them.
Many reach a goal (graduation~), don't know what's really next, look around at nearby peers/family, and simply emulate what they see.