"If you vaccinate someone, and they make an antibody response, and then they get exposed and infected, does the response that you induce enhance the infection and make it worse? The only way you'll know that is if you do an extended study [not on volunteers, but on the public]."
Then you said: "That's how trials work. Controlled experiment with large N. In the public."
My contention: it is no longer a controlled experiment when you release it to the public, without a control group. Now, you can still change policies or advisements based on data once it's in the wild, but that's no longer an "experiment" nor a "controlled study" nor a "trial".