The meme has a point: leaving aside the hospital strain issue for a moment… Joe Rogan mostly harms his listeners. Why do the rest of us care?
The best hypothesis I have at the moment (about why we should care) is the (debatable) hypothesis that public education benefits us all, and Joe Rogan is the exact opposite of public education.
Being in vaccine discussion groups with anti vaxxers and the vaccine hesitant I'm not sure the meme has it right even if we ignore the externalities of infected unvaccinated. It isn't so much people taking medical advice from Rogan but that he platforms "experts" that sound legitimate. And what they say goes from the Rogan listener to others around them that just see "doctors" saying things that sound possible and alarming.
I feel like the meme doesn't fully appreciate the knock-on effects of misinformation. The downstream people hearing the misinformation may have no idea who Rogan is. But their friend/family member that they trust who is a Rogan fan is telling them something and seemingly has "data"/"studies"/"experts" to cite.
See for example the myocarditis vaccine stuff Rogan was talking about that really bastardized the topic. He was citing the Nature study, just selectively and without context, and was citing Vinay Prasad, who again bastardized the topic.