I do agree with it in principle: that the people most at risk of serious illness and death should be vaccinated first. But at an individual level, I don't think the risk always fits neatly in the categories.
For instance, 65 year old working from home has priority over a 64 year old diabetic with heart and kidney disease, with occupational exposure (but not health and social care).
A healthy 25 year old working in a care home has priority over a 90 year old with dementia.
The group 6 category doesn't take account of the increased risk of multiple conditions and age. Occupational exposure isn't considered outside the defined groups (maybe the main aim of vaccinating carers and health and social care is to protect the people they are caring for, rather than themselves).