I hadn't heard of this before.
A 'double dignity' job is one that offers a worker the dignity of meaningful skilled work in the cause of closing dignity gaps for others.
For example: home care for those older loved ones with dementia, specialized care and assistance for children and young adults with Down Syndrome, quality pre-school instruction, and on-going individualized help for children from lower income backgrounds who never get true first or second chances.
Skilling up such care jobs—As SEIU President Mary Kay Henry has long called for—can lead to higher wages, more satisfying careers, and can reduce national health-care costs. And if the more severe predictions of structural reductions in the demand for labor do come true due to automation, AI, and robots, wouldn’t it be better to target our resources toward creating new jobs that have the dignity of, as Dr. King said, serving humanity?
These ideas are laid out in this article by economist Gene Sperling.
OT definitely fits into this category.