Ivermectin is not a standard of care covid treatment, or prevention. Based on the available medical data at this time, just like hydroxychloroquine and chloroquine, it has not been shown effective for treating or preventing COVID-19, yet. It is hard to imagine it would ever be used or approved for covid prevention but anything is possible.
I would hope that anyone interested in ivermectin would choose to participate in a controlled clinical trial that would benefit all.
clinicaltrials.gov
We certainly have free will, but that has nothing to do with how clinical studies are designed and/or run.
Fauci is not a God Almighty but he is an excellent scientist and, just like the guys who fly rocketships to Mars and then launch a helicopter, he uses hypothesis driven research to draw mechanistic conclusions - to inform his decision making process. It's not different than engineering - for example designing, building, testing engines. It's not foolproof, either.
A hypothesis is just an educated guess, but - it needs to be
testable, have a "null hypothesis". Hypothesis-driven medical studies are a very powerful, and currently the best way to figure out what works and what doesn't.
Natural antibodies, aka IgM, are generally low-affinity, high avidity, pentameric protein machines that can clear certain infections but are not great at clearing viral infections and do not provide long term immunity or immunological memory/recall responses; for various reasons clearing viral infections requires cooperation between B and T cells to make, among other things, high affinity abs (hypermutated and class-switched) that provide long lasting anti-viral effector responses / immunity. I'm scandalously oversimplifying things, but the bottom line is this: no, one's natural immunity is not great against covid, and yes - the vaccination improves one's immunity GREATLY.
--