No, it couldn't - largely because of inadequate supply initially - but then it was shown to be largely ineffective in terms of outcomes.
There was not an inadequate supply, initially or otherwise. There
might have been, had it been determined that hydroxychloroquine were to be the primary therapeutic for covid, but that didn't happen. Hydroxychloroquine is cheap and easy to make, so ramping up production to meet demand was never an issue.
As for being shown to be largely ineffective, when used without zinc or with patients already on a respirator, it's not effective at all. But when used in high doses, along with zinc, and given early on after a positive test, it's shown to be very effective in reducing hospital admissions, need for respirators, and deaths.
It is used to treat a number of auto-immune diseases (like lupus) and when Trump irresponsibly commented on it's potential use for COVID (based on anecdotal reports), huge numbers of idiots rushing to their doctor to get a 'script created such demand that the people that actually needed it - who had a disease that it was approved to treat - had trouble getting their prescriptions filled.
For one, if it was based on anecdotal evidence, then commenting on its
potential use for covid would not be irresponsible. Two, the supply and demand problem lasted about 2 weeks. 4 of the 8 hydroxychloroquine suppliers had adequate supply, and the 4 that didn't was able to ramp up supply to meet the demand.
One of the idiots, an Arizona man - that listened to The Orange Idiot - ended up dying ... from a version of chloroquine used as a parasite treatment for aquarium fish that he and his wife took. That's real jenius ... with a capital J.
That's Fake News. The Arizona man was unknowingly fed chloroquine phosphate poured into his soda by his wife. His wife initially said that she did it after listening to Trump, but it turns out she's an anti-Trump Democrat with a history of vitriol against Trump in particular and Republicans in general. Homicide detectives are still investigating.
The drug has potentially significant, and possibly life-threatening, side effects, hence the withdrawal of the Emergency Use Authorization.
"Hence" isn't the reason for withdrawal of the EUA. The known side effects was a factor, but not the primary factor. The EUA was specifically for use in hospitalized patients with advanced covid symptoms and based on the data they had at the time that hydroxychloroquine didn't have much of an effect on those patients, they removed the EUA.