This thought experiment is fundamentally flawed if it doesn't take into account that if just under half of humanity was killed, society would come to a 100-to-zero halt and the rest of the population would die from the sudden severance of every supply chain. Even if they were a substantial minority, the immediate loss of as low as a quarter, or probably even a fifth, of humanity would be an apocalyptic event.
Electricity out within a day. Tap water no longer drinkable due to a lack of people to run the purification plants; bottled water looted from every store. No more gas trucks, so when your local station runs out, everyone's out. And also, assuming the blue voters aren't Thanos-snapped away just hope your death won't involve a horrific infection from the corpse juice accumulating on every flat surface.
There's a fable about selfishness in there.