Actually, there are 2 big issues with it. First, as you mentioned, Donald Trump had something good to say about it, which is enough to trigger those with TDS. The biggest driver though IMO, is the fact that it is a 60 year old medicine for which there are no patents to encumber the production of it, and allow Big Pharma to jack up the price. Since the proper pockets are not going to be sufficiently lined, they are opposed to its use.
I've been laughing at these morons who are freaking out about a well known, and very well understood drug. We have 60 years of experience with it. We know how it affects people in ways that we'd never know with some brand-new shiny (patented) drug.
The third big problem is it could have ended the epidemic and shutdown. It was a prophylactic that makes stay-at-home, masks, social distancing, mail-in-voting rally cessation, and Joe-in-hiding ALL unnecessary. I am sorry to say DJT has not surrounded himself with competent advisors who could have all this in March or April at the latest.