To be fair, even though Trump disregarded most public health measures he was an advocate of vaccine development and really did grease the skids to make it happen.
In Dec 2020 my left wing friends were expressing fear of a vaccine that Trump developed at "Warp Speed". After Biden was inaugurated anti-vax became a right wing thing. Trump could have done some good using every channel to push people to take "his" vaccine but he choose not to because, I think, he understands that QAnon psychology and knows he would lose the esteem of his Jan 6 army if he did something responsible.
It's like the story of the Church of Scientology where it's believed the leader, David Miscavige is terribly afraid of catching COVID and has driven the staff to take extreme precautions against it, including mandatory vaccinations. He's also told staff to lie about this because he believes the Scientology public is anti-vax and would be driven away if they were honest.