> Vaccines that target new infectious agents are often tested using the placebo method, but for well-known and researched diseases, health experts say using a placebo poses ethical issues because the group receiving it will not know if they are actually protected against the illness.

...

> Peter Lurie, a former Food and Drug Administration (FDA) official, told the BBC, “It’s hard to tell exactly what is being proposed.”

> “But, broadly, if they mean that every modification to an existing vaccine would require a new placebo-controlled trial, they are treading in ethically dubious territory and likely to deny Americans life-saving vaccines at some point.”

So grandstanding without nuance. It's a clear pattern with this US admin.