Regarding the zinc deficiency; we see a large variation in outcomes after infection. Part could be viral load, but since we know people with "comorbidities" are more vulnerable to bad outcomes this delta should be an area of interest. Some people are totally asymptomatic!
The comorbidities (let's say heart disease) are caused by environmental or genetic variables. It seems zinc deficiency, to me, might be a common thread to both comorbidity and infection outcomes.
Since ACE2, a zinc metalloprotein which uses zinc as a cofactor, is in the alveoli and is the receptor for the virus, it would make sense to look at this as a serious possibility. ACE2 is a "Therapeutic Target for Heart Failure" https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3944399/
And zinc plays a role in the lung disease as well:
https://link.springer.com/article/10.1007/BF00944606
Interleukin-1α (IL-1α) production by alveolar macrophages in patients with acute lung diseases: the influence of zinc supplementation
"These results suggest that zinc can regulate the production of IL-1α from AM in patients with pulmonary tuberculosis or bacterial pneumonia."
Both anecdotally and experimentally there is evidence that zinc inhibits the replication of several virii. So zinc deficiency might make infection more likely and weaken the immune system to make outcome worse.