I’m thinking more about the single woman who is on her own, whose parents are deceased and who has no social safety net in terms of siblings or extended family.  

I understand and I believe its a very hard and sad situation.
In a catholic world, a single woman was never alone, because she had siblings, extended family or were able to become religious.
My parents had single aunts and they :
A- Lived with a married sibling
B- Lived with their parents, taking care of them and remaining at the family home. Grandpa left the parents home to the unmarried sister when their parents died)
C-One was a primary teacher and was able to earn some money
Married sons NEVER let alone their unmarried sisters, so parents could be calm. Having a degree was an exception...
So, solution in the future is raising catholic families with all the children God sends and telling our sons they could never abandon their sisters and protecting unmarried sisters by testament (you can give more percentage of property).
Even with the money you have to pay to go to college you can start a small bussiness to your daughters or handicaped sons , etc...