Excess LDL and VLDL cholesterol have absolutely been shown to be harmful. We know from studies of familial hypercholesterolemia, a disorder caused by single mutation in the LDL receptor gene, that too much LDL cholesterol directly leads to artherosclerosis and early death from heart disease.

There's a pretty direct analogy to type 2 diabetes and metabolic disease generally. The human body naturally produces blood glucose and we would quite quickly die if our blood glucose levels went to zero. That doesn't mean that hyperglycemia is healthy and in fact, we know it directly causes all kinds of bad health outcomes. We absolutely need some LDL cholesterol, and in our evolutionary history when we faced famine there was probably some selection for people whose livers didn't aggressively metabolize LDL particles from the blood (an energetically costly process), but that doesn't mean that high LDL cholesterol today is safe if you're hoping to live a long life.