Good analysis of a much misunderstood topic. But herd immunity might be closer than we think. I've recently read several research articles claiming that many of us have carried this or similar viruses for a long time but our immune systems have handled it. And yes I'm aware there is just as much research contradicting this.
One item I read earlier today referred to all human individuals carrying trillions of viruses at all times, most of them totally harmless. Have to admit that seems a bit of a crazy figure, but the more I read the more I find biologists really understand very litttle about these tiny organisms.
But that has been the case throught the months of this crisis. Nobody seems able to give any firm prognosis of how the pandemic will develop.
I'll just keep easting my healthy diet with plenty of probiotics and trust my immune system.