Because of natural immunity from in at least 1/3 of Americans, maybe 40%, who got COVID and got over it, most of them easily. What is the second reason? Because 65% of Americans have had at least one dose of vaccine. That's a big part of what makes the chance of getting COVID lower for everyone, vaccinated or not. Leaving that out is a lie of omission.
And you can add another category. Due to the CV being about 60% the common CV strains that already existed, there are also people who already had sufficient antibodies needed per Dr. Yeadon.
The average lay person has no idea what determines true efficacy. To label an experimental modality the way its being marketed borders on criminal behavior. Just because you can do something doesn't mean you should. If enough people end up being hurt or killed the blow back will be extreme.
The whole process will undermine the physician-patient relationship for years. Welcome to the low trust society.