Comorbidity would include conditions like old, obese, or asthmatic. The argument du jour is that COVID isn't real because it is comorbidities that are the real cause, sort of a more subtle twist on the "doctors are falsifying documents" argument.
It's another wave of nonsense and misinformation. Allow me a comparison.
Imagine that you lived on the British Isles in the year 1000 or thereabouts. Vikings periodically invade to rape, pillage and kill. You're trying to discuss this problem.
"This is an atrocity. They killed Elwood and raped his wife and stripped everything valuable from his farm."
"Well of course they killed Elwood."
"Comorbidities. You know how scrawny Elwood was. I mean, of course he couldn't stand up to a Viking attack."
"You're saying that he wasn't killed by Vikings but instead because he wasn't sufficiently buff?"
"Essentially, yeah. I mean, it's almost always the scrawny or old guys who are most likely to die."
"And the convent of nuns they attacked and raped?"
"Well, nuns. I mean. They have almost no upper body strength."
"Which explains why the Vikings raped and pillaged their convent?"
"And the problem isn't that Vikings are raiding our coast raping and pillaging?"
"Vikings are going to rape and pillage. Vikings are going to do what they do. You aren't going to change that."
"You don't think that maybe we could form some kind of coastal defense so that it isn't so easy for the Vikings to attack us?"
"That seems like a lot of hassle. And sounds very expensive. Just keep a broad ax handy. And do something to increase your upper body strength. You are not going to have much luck fending off Vikings."
Comorbidities is a fancy way of saying, "COVID is more likely to kill people who are vulnerable." It's self-evident nonsense presented as if it is insightful.
COVID raises the probability of death the same for everyone. It is true that different groups - young and fit high on that list - are less vulnerable and increasing their odds of dying still leave them highly unlikely to die compared to, say, an asthmatic 94 year-old who is incredibly vulnerable. (And of course death isn't the only bad thing that can happen. Long COVID can change your health for ... well no one really knows for how long.)
Saying that the vulnerable are more likely to die of any cause is not an explanation or an insight. It's just another way to dismiss COVID - a disease that has lowered life expectancy in the US for the first time since 1918 - rather than acknowledge its severity and impact.