> The initial premise of the "flatten the curve" memes was to avoid overwhelming hospitals.
I don't think it was a 'meme' - if you're thinking it was just something on Facebook or something like that. It was and still is a government goal informing their policy.
Setting aside Dawkins, and looking beyond image macros, it seems to me that the meaning of 'meme', in it's common usage, can encompass the meanings of "message", "claim", "idea" and more. It's not necessarily dismissive, and can sometimes emphasize the simplicity of structure or frequency of use.