Charley Hooper is on a small listserv on which I also am sometimes active. I share here (with his kind permission) a note that he sent out earlier today in a thread discussing naturally acquired immunity and immunity that is gotten through vaccination.
Three small points that might help:
The normal goal of vaccines is to replicate natural infections without the actual infection. In other words, natural infections are the gold standard and good vaccines equal or come close to the immunity provided by natural infections.
No one wants a natural infection with SARS-CoV-2. But now that some have had it, they have a level of immunity. Based on the evidence I’ve seen, their immunity is probably better than that from the vaccines.
See the attached graph. [Available here: COVID Timeline.] It shows how antibodies wane over time (they are expensive to keep around) while T cells (cheap to keep around) remember the infection for much longer, often decades. Our immunity to some diseases lasts longer than our lifespans. By the way, humans have the best immune system among living beings. Our immune systems can remember some astronomical number of contagions—something on the order of 100 billion different types of germs. It’s really pretty amazing.