They’re almost 50 and don’t have a full time job with pension. That is not a good position to be in unless you come from money, are married to someone who does, or has a solid professional career or gold plated benefits and a permanent job.
They spent 30 years "working" on their research interest instead of at the beck of bosses and clients. Even if they spend retirement stuck as a grocery clerk, they'll have a better life (more funded free time to pursue their personal interests) than almost everyone.