Yes, many older doctors have gone part time or retired recently, and younger doctors may have young children and so work part time, but don’t make the mistake of thinking all do. Most hospital doctors work full time and GPs work 11/12 hour days so four days a week is full time for them. My daughter works three jobs, one as a GP, one as a private consultant at a private menopause clinic, for which she did an extra qualification which she paid for herself, and also she works some evening shifts at ED (our A+E) because she’s presently living and working in New Zealand and her marriage has broken down, leaving her in the position of doing a lot of work. Not all doctors by any means have gone part time or retired.
My sons both work many hours too. None of my children expect the state to pay their mortgages or to up their wages. Not many single people in their thirties can afford to work part time and pay their rent. The OP says this person has no savings or pension. It seems highly likely that therefore she’s going to need some state funded help, and unless she’s unable to work full time for health reasons, that is inexcusable. It doesn’t matter if she’s going to write a book, or just enjoy herself, her first duty is to support herself and not expect tax payers to step in.