Read a very interesting article the other day...can’t find it right now. But the gist was this.
Your immune system comes in two waves. First wave is from the cells. Basically a self-destruct...when infected they send out a chemical signal that shuts down adjoining cells. Vastly reduces viral replication and buys time for the second wave to rally up...white blood cells and such.
Anyway, the reason COVID produces so many negative outcomes is because the first wave never happens. Somehow it bypasses it and by the time the second wave hits the virus is too widespread. The immune response overloads and you get the dreaded “cytokine storm”.
So to the point, even a mild antibody response would be helpful. Even after the virus mutates...which it will.