Probably quite a few. A lot of people have significant decrease in cardiopulmonary function over their life, and as I have told people “age is a pre-existing condition”. I also believe that the whole “smoking changes the ACE2 receptors in the lungs” has been wrong the whole time. Smoking damages the lungs and reduces their efficiency, making you less likely to survive a severe lung infection. Also note that heart disease is the #1 co-morbidity. Basically, any condition that weakens your cardiopulmonary system is going to be a significant co-morbidity. Age, smoking, asthma, emphysema, COPD, heart disease, pulmonary fibrosis, chronic bronchitis, etc.
Obesity is also the wild card in the deck—untested in the wild with this disease.