Every country that had cases of the virus peaked then fell.
Many are now getting a second dose, and numbers rise again, and when it is under control, they will fall again.
Can't see this as earth shattering, or something to brag about regarding predictions.
Seems pretty obvious to me.
Up, then down.
Just like the Stock Market.
Even a dumbo like me can work that out!
Another point of view regarding herd immunity.
Coronavirus: Spanish study casts doubt on herd immunity feasibility - BBC News