I am not an expert. I know less than the Director of the National Institute of Health and the Director of the CDC. I defer to them as the best source of information about everything related to Covid.
Having said that, I believe that everyone, and I mean everyone is going to get Covid.*
People who have been vaccinated are mostly going to get mildly sick, and people who have not been vaccinated are going to get badly sick in pretty significant numbers.
We will get to 100% herd immunity in the near future, because 100% of the entire population of the country is going to get Covid.
The pre-Delta-variant would have spread the virus more slowly and with less deadly consequences, but this Delta-variant is going to move at NASCAR speed with serious-as-a-heart-attack consequences.
*There may be a small percentage of the population who has a natural immunity to Covid. I don't know whether that is true or not. But everyone, and I mean absolutely everyone who does not have a natural immunity to Covid is going to get it.