IIRC there's some evidence that cold temperatures weaken the immune system. Assuming it's valid, that does mean that cold could be the deciding factor between contracting a cold or fighting if off.
Now obviously germ theory is correct and it takes external infection to catch a cold, but it's a pretty safe bet you're being more or less constantly exposed to COVID and the flu whenever you're in an indoor public space.
Do you realize what comm you're in?
If pointing out that EVs aren't a real solution is enough to alienate those "allies" they weren't really allies at all. It's also less about individual choice to move to areas with better transit, and more about pressuring the government to install better transit everywhere instead of just funneling endless money to car manufacturers.