Here is my layman's take on this. It is not my field but this is what I understand.

I think that doing a massive distribution of a vaccine in the middle of a pandemic, when the virus is everywhere is a recipe for variants. The vaccines target just one single protein in the virus, the spike protein.

So when everybody has at least some of these viruses in them there are going to be mutations of that one protein that cause the antibodies to fail to identify it.

That variant virus can multiply and spread to other vaccinated people without being hassled by the vaccine-induced antibodies.

Natural immunity is different. By the time you fight it off your body has discovered multiple targets for the antibodies. It is much less likely that a mutation would have multiple different proteins in the right combination to avoid the antibodies.

So if they had just done the normal thing...

Emergency use authorization for Hydroxychloroquine and Ivermectin. Issued guidance for general practitioner doctors to prescribe that with zinc plus vitamin C and D. Hospitals wouldn't have had to shut down their money-making elective procedures.

Then the FDA could have studied the vaccines for 9 years and done honest evaluations of the safety. At that point, the pandemic would have been long over.

With most people now having natural immunity and the virus not widespread, maybe a vaccine could work without causing variants. Not these vaccines though because they would never have made it through proper FDA testing.