>It would also have meant that the curve would be flattened for good.
I have yet to see any evidence that covid antibodies provide long-term immunity. We can't say with any certainty that the curve would be permanently flattened. It may just be flattened for a few weeks, a few months, or a few years.
> if these antibodies actually mean long-term immunity
This is the big unknown that seems to be largely ignored, thank you for bringing it up. I am frequently seeing "herd immunity" thrown around without any qualification on the durability of the associated antibodies.
User "Touche" asked what he is missing to be convinced that the virus will disappear: he is missing delusion.