I know nothing about medicine, but is there any way to skip the lungs and give patients oxygenated red blood cells directly?
Human bodies are just too damn complex. Even when the problem is clearly identified--a lack of oxygen in the blood--there's no way to just insert more that doesn't cause a hundred new problems :-/ Natural selection seems to be really bad at modular design.
Or the other way around, modular design does not appear to be a requirement for "success.". We like it for the reduction in complexity but that is ultimately a tradeoff.
So putting someone on an oxygenator might condemn the patient to stay on one until the virus kills them.