Yes, and it is more common than most people on the outside realize.
A significant portion of the incarcerated population does their entire sentence completely alone. No visits, no phone calls, no letters. Nobody putting money on the commissary account, nobody checking in, nobody counting down the days with them. They go in with whatever connections they had and watch those connections quietly disappear over months and years until there is nobody left.
It happens for all kinds of reasons. Long sentences that outlast relationships. Family members who are struggling themselves and cannot afford calls or visits. Estrangement that predated the incarceration. Shame on both sides that makes reaching out feel impossible. Geographic distance that makes visits impractical. And in some cases, people who simply never had much of a support network to begin with and whose incarceration made that isolation permanent.
The correctional system has no mechanism for addressing this. Staff are not there to manage the social lives of inmates. Corrections officers are focused on security, order, and getting through the shift. Reading inmate profiles or facilitating social connections is not part of the job and is not something the institution invests in.
What fills that gap in a limited way are pen pal programs, faith-based outreach volunteers who come into facilities, and organizations that specifically work with isolated inmates. InmateAid's platform is used by people who reach out to strangers inside for exactly this reason.
Doing time completely alone is one of the hardest versions of an already hard experience. If you are thinking about reaching out to someone who has no one, that impulse is worth following.