I think it's just the idea of endorsing prophylactic medicine. Since anyone could be a potential victim of a virus, everyone should consider vaccination. And while it's not compulsory, the suggestion that it be widely advocated sets the conspiracy folks on edge. They seem to pin their identity on { I'm not like the others + mistrust of authority }. So it's really easy to accept a message that the too-trusting have all fallen into a trap that they're too smart for. If it's not tracking, it's greed, or some other motive driving evildoers to vaccinate the world.
Hydroxychloroquine was attractive because it was available before the vaccine and you would only need to administer it to the infected. Of course, a few did try to take it prophylactically and at least one OD'd.
Trump is so purely and consistently self serving. He didn't promote the vaccine enough because he feared his successor would get the credit and he (rightly) feared his base would hold it against him. And he only promoted it when he realized that his supporters were dropping like flies and millions of the kids in the next generation will turn eighteen before the next presidential election.
The vaccines are a triumph of humanity that should be celebrated. They were produced, tested and distributed very rapidly (among the wealthiest countries). We could stand to improve significantly at how well it was distributed to poorer nations. But IMO a positive story overall. And antivaxxers might have had reason to be cautious at first, but now it's so widely distributed that it doesn't make much sense to fear it anymore. the long term consequences of the infection are likely much much worse than the long term consequences of vaccination.
Not GP (although I agree with them), but Trump's words and actions over the past 40 years or so make it quite clear that Donald Trump cares about three things:
1. Donald Trump
2. Donald J. Trump
3. Donald John Trump
and everything else is just background noise, if that.
