Some people would say that at least Trump authorized Operation Warp Speed which led to the amazingly quick development of vaccines.
Yes, he did lift the pen and sign some documents, though the real heavy lifting was from many people, including great scientists.
Something he didn't do could have led to success as well. He, and Republicans in Congress, could have been such deficit hawks as to refuse government funding for research. 3 trillion dollars was made available, last spring, for relief efforts; including the research.
It made my head spin that even "the Grinch that stole Christmas," Mitch McConnel signed onto that original relief bill. Some folks might say that government has no role in helping us. Let the private sector do this.
From what I understand, the first vaccine, produced by Pfizer, was more privately funded; rather than from the Operation Warp Speed research grants. Still, according to an NPR show I heard, Pfizer benefited from the community of research that's happening. Having a proven vaccine, the government is now buying doses, from Pfizer, for public distribution.
Vaccines from other pharmaceutical companies, such as the hopefully soon to become available Moderna Vaccine, came more directly from the Operation Warp Speed efforts. There are even more versions of the vaccine in the pipeline. Big pharma is another controversial thing in society, but it seems to be coming through when we need it.
Both government and private enterprise play valuable roles in our economy.