(Speaking of vitamin D, I personally did exactly that with vitamin D + vaccine. My doctor told me a few years back I was low on vitamin D and should supplement anyway, and the vague evidence that it maybe helps against covid was enough for me to decide to take it regularly at a high dose, because there aren't really any downsides besides getting through my bottle faster. But I also got the vaccine!)

If ivermectin was found to be safe and effective and got FDA approval itself, the vaccines of Pfizer, Moderna and J&J would need to get full approval - meaning longer and more rigorous clinical trial and safety testing. (not that they haven't gone through a certain level of those things, just the bar is set lower with EUAs)

p.s. Sounds like you talked to your doctor about supplementing VitD - but you're mistaken to say there aren't any downsides (especially for regular high doses of D) --- It can cause hypervitaminosis D which in turn causes hypercalcemia (a buildup of calcium in your blood). Just saying as it may be worth double checking :)

We do have an alternative that works in theory - if everyone wore an N95 (or knockoff, even!) mask at all times in public, indoors and outdoors, and if all restaurants did takeout only, the risk of transmission would be extraordinarily low. And it's not zero even with the vaccine. The vaccine does different things from masks, though.

I think money-grubbing Big Pharma execs who were recently regulators on the other side of the revolving door would easily be able to argue that ivermectin (or vitamin D, or whatever), useful as it may be, is not an adequate alternative to the vaccine, just (as you put it) another facet in a multifaceted approach, and the vaccine still needs an EUA.