I have recently heard that a dietary restriction of any kind tends to improve health outcomes (i.e. lower diabetes incidence) as they all tend to have one thing in common: thinking about what you eat.
That isn’t to say that cutting meat could have a more significant effect. I’m just saying that people who give little to no thought about what they eat will likely be overrepresented in those with diabetes (maybe the article addresses this; I couldn’t read it).