One notable shortcoming of Ivermectin, is that you have to continually take it (I believe weekly) to stave off COVID-19.
As widespread as the disease is already, and the fact that there are many common animal reservoirs for COVID-19 (including dogs, cats, deer and bats - probably cattle, pigs and rodents as well), means that it won’t likely be contained or go away, until the great bulk of people have been exposed, and developed immunity.