There is a huge correlation between people low in Vitamin D and bad COVID-19 outcomes, correlation != causation, sure. It’s usually too late to expect giving vitamin D at the point of hospitalisation to expect it to help. I’m for most people taking vitamin d regularly for all sorts of reasons. I’d be much more circumspect about Ivermectin but the studies are being done now to see if it can help, to say it absolutely won’t work is unknown. I think promoting it is pretty bad personally and I don’t take my medical advice from Joe Rogan. Medcram is pretty informative though.