HashemLovesMe-
As I posted in another thread- my brother and sister-in-law are able to make ends meet without support from either set of parents or the government.
My sister-in-law got a mail order diploma and my brother learns full time. I don’t know specifics about their finances but I do know that he goes to a morning kollel and night kollel and takes bechinos on the material that he learns to earn some extra money. My wife suspects that he also tutors during his free time.
They live on what I consider to be the bare minimum.
(They also pay full tuition albeit it is cheaper in Lakewood than Brooklyn.)
If a couple wants to be moser nefesh for learning and they are serious about it, it can be done without external support. But it does mean giving up on allot of gashmius.