What if someone in your house bumps into a non-mask wearing Trumper in public and that person transmits the disease. Who's fault is that?
The answer to your examples is yes it is those people fault. However since the country is not in the position to isolate themselves completely from others their actions effect others. The odds are so infinitesimal you hit me base jumping and kill both of us I'm confident in advising you "feel free to jump off a cliff"
Is it your contention Trump bears zero responsibility for the COVID spread in this country?