>>After all, the cells in our body do need glucose to survive, no?

Neurons seem to rely on glucose - but that does not mean we need to eat glucose. Our livers can convert fats into glucose, and once there is no more fat (starvation), protein as well. This system of glucose production is triggered by glucagon from alpha cells in the pancreas (then no insulin from the beta cells is how the body ensures the glucose being produced isn't consumed by cells that can otherwise use ketones.

If you have high fasting glucose, it's most probably due to alpha cells producing glucagon which is causing the liver to make too much glucose.

Not someone with bio credentials, just have been reading studies since my dad was diagnosed with T2DM 30-ish years ago.