Yes, it's entire possible that the "cytokine storm" hypothesis turns out to be wrong. Here's my inexpert summary of what some researchers believe: A buildup of superoxide radicals leads to a buildup of other "reactive oxygen species," all of which cause acute oxidative stress—notably in the endothelia.

So COVID-19 attacks the endothelial structures throughout the body. Notably the interface between lungs and blood vessels, but also the heart, other vital organs, capillaries, etc. Hence clotting and "sticky blood" is a huge problem.

Unsurprisingly, bad diet messes up one of the pathways the body uses to cleans up superoxide radicals—chronic high sugar and lack of trace elements (zinc, copper, magnesium). And now it seems C19 messes up another pathway, thanks to it interfering with ACE2 receptors. This could be why we're seeing high mortality in people with diabetes, pre-diabetes, and all the other conditions related to poor blood-sugar regulation—obesity, coronary artery disease, dementia, etc.

A good summary at: https://www.youtube.com/watch?v=Aj2vB_VITXQ