The first trump administration still had a mostly intact bureaucratic apparatus with a cadre of career technocrats in positions of authority and influence. The second is oriented very differently.

Also remember that the politicization of masking took a while to spin up, and didn't fuse with and evolve into the current antivax movement until later, when the vaccine was actually in sight. It wasn't a bipartisan wonderland or anything but early covid days was an extremely different political environment from now.