I work in an area related to administration of deceased peoples affairs.
Every day I deal with cases where people have died alone. Not found until their house starts smelling etc, sometimes for months.
They don't have visitors and they don't have family. But as they own their homes and pay bills by direct debit there isn't a flag raised.
They are on their own for myriad reasons. Some have outlived their families, moved away or never had family.
Some preferred privacy and refused anyone access to their home. I hear neighbours say again and again 'he kept himself to himself'.
Many neglected their health problems and refused approaches from people who could help.
Each case is different and each case is sad, but none of the cases I work with are related to poverty or benefits etc. Life is complicated, and many people can't be 'fixed' by any higher power.