This is exactly like those stupid "Stand Up To Cancer" commercials I used to see- and actually commented on more than a decade ago. You know, the ones where random people (and Lance Armstrong) would stand up and stare at the camera and challenge cancer to a fistfight, or something.
This really weird anthropomorphizing of a disease always struck me as being weird. I have rheumatoid arthritis. My specialist never suggested to me that RA was "out to get me" and it was "me against RA" or that shooting up with Humira twice a month was my way of "fighting back" against RA, maybe because he's an adult and I'm an adult and he realized that to describe my condition and it's treatment in that manner would be treating me like a child. Instead, he just told me that Humira can aid in controlling the symptoms of RA. He didn't describe RA as a monster that had invaded and was determined to take over my body and "control me." And I'm grateful that he didn't because I prefer to take my doctor seriously.
To the best of my knowledge, diseases don't exist to challenge us or knock us off our pedestals as the Most Awesomest Living Things Ever. They don't exist for any purpose at all, and they aren't thinking at all, let alone thinking of ways to bring us down. To think otherwise requires a level of self-importance even I can't obtain.
On the other hand, if phrases like "Win The Fight Against COVID" and "Defeat COVID" and "It's Us Against COVID" convince the roughly one-quarter of the American population currently determined to let Stupid enslave them (and, more importantly, make life difficult for the rest of us,) then I say keep using them. But I'm not going to stop thinking that this is all pretty stupid.